WO2013019088A2 - Method for setting an mtc terminal search area in a wireless communication system and an apparatus for same - Google Patents

Abstract

The present invention relates to a method in which a terminal receives downlink control information in a wireless communication system. The method includes the steps of: receiving control information masked with an identifier of a group to which the terminal belongs in a first area of a subframe; setting a group-specified search area of the group to which the terminal belongs in a second area of the subframe according to first control information; and receiving group-specified downlink control information on the group to which the terminal belongs, wherein the group-specified downlink control information includes resource allocation information for each terminal belonging to the group.

Description

Method for setting search area of MTC terminal in wireless communication system and apparatus for same

The present invention relates to a wireless communication system, and more particularly, to a method and apparatus for setting a search space of a machine type communication (MTC) terminal in a wireless communication system.

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 Evolution (LTE)) communication system will be described.

1 is a diagram schematically illustrating an E-UMTS network structure as an example of a wireless communication system. The Evolved Universal Mobile Telecommunications System (E-UMTS) system is an evolution from the existing Universal Mobile Telecommunications System (UMTS), and is currently undergoing basic standardization in 3GPP. In general, the E-UMTS may be referred to as a Long Term Evolution (LTE) system. For details of 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 (AG)). It includes. The base station may transmit multiple data streams simultaneously for broadcast service, multicast service and / or unicast service.

One or more cells exist in one base station. The cell is set to one of bandwidths such as 1.25, 2.5, 5, 10, 15, and 20Mhz to provide downlink or uplink transmission services 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 for downlink (DL) data and informs the user equipment of time / frequency domain, encoding, data size, and HARQ (Hybrid Automatic Repeat and reQuest) related information. In addition, the base station transmits uplink scheduling information to uplink UL data for uplink (UL) data and informs the user equipment of time / frequency domain, encoding, data size, HARQ related information, and the like. An interface for transmitting user traffic or control traffic may be used between base stations. The core network (CN) may be composed of an AG and a network node for user registration of the terminal. The AG manages the mobility of the UE in units of a tracking area (TA) composed of a plurality of cells.

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 evolution is required to be competitive in the future. Reduced cost per bit, increased service availability, the use of flexible frequency bands, simple structure and open interface, and adequate power consumption of the terminal are required.

Based on the above discussion, the following is a method for setting a search area of an MTC terminal in a wireless communication system and an apparatus therefor.

In one aspect of the present invention, a method for receiving downlink control information by a terminal in a wireless communication system includes: receiving, in a first region of a subframe, control information masked with an identifier of a group to which the terminal belongs; Setting a group specific search region of a group to which the terminal belongs in the second region of the subframe according to the first control information; And receiving, in the group specific search region, group specific downlink control information of a group to which the terminal belongs, wherein the group specific downlink control information includes resource allocation information for each of the terminals belonging to the group. Characterized in that.

Here, the first control information includes information about a start point of the group specific search region, and the start point is changed by a predefined rule for each subframe based on an identifier of a group to which the terminal belongs. It is done.

Preferably, the method may further include receiving an index of the terminal from the group through an upper layer, wherein the group specific downlink control information includes the resource allocation information for each of the terminals belonging to the group. Characterized in the order of the index. In addition, resources for each of the terminals belonging to the group may be regularly allocated in a predetermined size unit.

On the other hand, the terminal device in a wireless communication system according to another aspect of the present invention, in the first region of the subframe, a wireless communication module for receiving control information masked with the identifier of the group to which the terminal device belongs; And a processor for setting a group specifying search region of a group to which the terminal apparatus belongs in the second region of the subframe according to the first control information, wherein the processor is configured to display the terminal apparatus in the group specifying search region. Acquiring group specific downlink control information of a group to which the group belongs, wherein the group specific downlink control information includes resource allocation information for each of the terminal devices belonging to the group.

Preferably, the receiving module receives an index of the terminal device in the group through an upper layer, and the group specific downlink control information includes the terminal index of the resource allocation information for each of the terminal devices belonging to the group. Characterized in order. In addition, the resource for each of the terminal devices belonging to the group is characterized in that it is constantly allocated in a predetermined size unit.

More preferably, the first region is a control region of the subframe, and the second region is a data region of the subframe.

According to an embodiment of the present invention, a search area for a machine type communication (MTC) terminal may be set more effectively in a wireless communication system.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned above may be clearly understood by those skilled in the art from the following description. will be.

1 is a diagram schematically illustrating an E-UMTS network structure as an example of a wireless communication system.

FIG. 2 is a diagram illustrating a control plane and a user plane structure of a radio interface protocol between a terminal and an E-UTRAN based on the 3GPP radio access network standard.

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

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

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

6 is a diagram illustrating a resource unit used to configure a control channel.

7 is a diagram illustrating an example of distributing CCEs in a system band.

8 is a view for explaining the structure of the machine type communication (MTC).

9 is a flowchart illustrating a method of receiving control information by an MTC terminal according to an embodiment of the present invention.

10 is a diagram for one example of mapping an E-PDCCH for an MTC terminal according to an embodiment of the present invention.

11 illustrates a block diagram of a communication device according to an embodiment of the present invention.

The construction, operation, and other features of the present invention will be readily understood by the embodiments of the present invention described with reference to the accompanying drawings. The embodiments described below are examples in which technical features of the present invention are applied to a 3GPP system.

Although the present specification describes an embodiment of the present invention using an LTE system and an LTE-A system, this as an example may be applied to any communication system corresponding to the above definition. In addition, the present specification describes an embodiment of the present invention on the basis of the FDD scheme, but this is an exemplary embodiment of the present invention can be easily modified and applied to the H-FDD scheme or the TDD scheme.

FIG. 2 is a diagram illustrating a control plane and a user plane structure of a radio interface protocol between a terminal and an 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 layer is connected to the upper layer of the medium access control layer through a transport channel. Data moves between the medium access control layer and the physical layer through the transport channel. Data moves between the physical layer between the transmitting side and the receiving side through the physical channel. The physical channel utilizes time and frequency as radio resources. Specifically, the physical channel is modulated in the Orthogonal Frequency Division Multiple Access (OFDMA) scheme in the downlink, and modulated in the 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 PDCP (Packet Data Convergence Protocol) layer of the second layer provides unnecessary control for efficiently transmitting IP packets such as IPv4 or IPv6 over a narrow bandwidth air interface. It performs header compression function that reduces information.

The 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 control of logical channels, transport channels, and physical channels in connection with configuration, reconfiguration, 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 UE and the RRC layer of the network, the UE is in an RRC connected mode, otherwise it is in an RRC idle mode. The non-access stratum (NAS) 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 the bandwidth, such as 1.25, 2.5, 5, 10, 15, 20Mhz to provide a downlink or uplink transmission service to multiple terminals. Different cells may be configured to provide different bandwidths.

The downlink transport channel for transmitting data from the network to the 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. have. Traffic or control messages of a downlink multicast or broadcast service may be transmitted through a downlink SCH or may be transmitted through a separate downlink multicast channel (MCH). 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. It is located above the transport channel, and the logical channel mapped to the transport channel is a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), and an MTCH (multicast). Traffic Channel).

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

When the UE is powered on or enters a new cell, the UE performs an initial cell search operation such as synchronizing with the base station (S301). To this end, the terminal may receive a Primary Synchronization Channel (P-SCH) and a Secondary Synchronization Channel (S-SCH) from the base station to synchronize with the base station and obtain information such as a cell ID. have. Thereafter, the terminal may receive a physical broadcast channel from the base station to obtain broadcast information in a cell. Meanwhile, the terminal may receive a downlink reference signal (DL RS) in an initial cell search step to check the downlink channel state.

After completing the initial cell search, the UE acquires more specific system information by receiving a physical downlink control channel (PDSCH) according to a physical downlink control channel (PDCCH) and information on the PDCCH. It may be (S302).

On the other hand, if the first access to the base station or there is no radio resource for signal transmission, the terminal may perform a random access procedure (RACH) for the base station (steps S303 to S306). To this end, the UE may transmit a specific sequence to the preamble through a Physical Random Access Channel (PRACH) (S303) and receive a response message for the preamble through the PDCCH and the corresponding PDSCH (S304). . In the case of contention-based RACH, a contention resolution procedure may be additionally performed.

After performing the procedure as described above, the UE performs a PDCCH / PDSCH reception (S307) and a physical uplink shared channel (PUSCH) / physical uplink control channel (Physical Uplink) as a general uplink / downlink signal transmission procedure. Control Channel (PUCCH) transmission (S308) may be performed. In particular, the terminal receives downlink control information (DCI) through the PDCCH. Here, the DCI includes control information such as resource allocation information for the terminal, and the format is different according to the purpose of use.

Meanwhile, the control information transmitted by the terminal to the base station through the uplink or received by the terminal from the base station includes a downlink / uplink ACK / NACK signal, a channel quality indicator (CQI), a precoding matrix index (PMI), and a rank indicator (RI). ), And the like. In the 3GPP LTE system, the terminal may transmit the above-described control information such as CQI / PMI / RI through the PUSCH and / or PUCCH.

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

Referring to FIG. 4, a radio frame has a length of 10 ms (327200 × Ts) and consists of 10 equally sized subframes. Each subframe has a length of 1 ms and consists of two slots. Each slot has a length of 0.5 ms (15360 x Ts). Here, Ts represents a sampling time and is represented by Ts = 1 / (15 kHz × 2048) = 3.2552 × 10 ⁻⁸ (about 33 ns). The slot includes a plurality of OFDM symbols in the time domain and a plurality of resource blocks (RBs) in the frequency domain. In the LTE system, one resource block includes 12 subcarriers x 7 (6) OFDM symbols. Transmission time interval (TTI), which is a unit time for transmitting data, may be determined in units of one or more subframes. 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 OFDM symbols included in the slot may be variously changed.

FIG. 5 is a diagram illustrating a control channel included in a control region of one subframe in a downlink radio frame.

Referring to FIG. 5, a subframe consists of 14 OFDM symbols. According to the subframe configuration, the first 1 to 3 OFDM symbols are used as the control region and the remaining 13 to 11 OFDM symbols are used as the data region. In the drawings, R1 to R4 represent reference signals (RSs) or pilot signals for antennas 0 to 3. The RS is fixed in a constant pattern in a subframe regardless of the control region and the data region. The control channel is allocated to a resource to which no RS is allocated in the control region, and the traffic channel is also allocated to a resource to which no RS is allocated in the data region. Control channels allocated to the control region include PCFICH (Physical Control Format Indicator CHannel), PHICH (Physical Hybrid-ARQ Indicator CHannel), PDCCH (Physical Downlink Control CHannel).

The PCFICH is a physical control format indicator channel and informs the UE of the number of OFDM symbols used for the PDCCH in every subframe. The PCFICH is located in the first OFDM symbol and is set in preference to the PHICH and PDCCH. The PCFICH is composed of four Resource Element Groups (REGs), and each REG is distributed in a control region based on a Cell ID (Cell IDentity). One REG is composed of four resource elements (REs). The RE represents a minimum physical resource defined by one subcarrier x one OFDM symbol. The PCFICH value indicates a value of 1 to 3 or 2 to 4 depending on the bandwidth and is modulated by Quadrature Phase Shift Keying (QPSK).

The PHICH is a physical hybrid automatic repeat and request (HARQ) indicator channel and is used to carry HARQ ACK / NACK for uplink transmission. That is, the PHICH indicates a channel through which DL ACK / NACK information for UL HARQ is transmitted. The PHICH consists of one REG and is scrambled cell-specifically. ACK / NACK is indicated by 1 bit and modulated by binary phase shift keying (BPSK). The modulated ACK / NACK is spread with Spreading Factor (SF) = 2 or 4. A plurality of PHICHs mapped to the same resource constitutes a PHICH group. The number of PHICHs multiplexed into the PHICH group is determined according to the number of spreading codes. The PHICH (group) is repeated three times to obtain diversity gain in the frequency domain and / or the time domain.

The PDCCH is a physical downlink control channel and is allocated to the first n OFDM symbols of a subframe. Here, n is indicated by the PCFICH as an integer of 1 or more. The PDCCH consists of one or more CCEs. The PDCCH informs each UE or UE group of information related to resource allocation of a paging channel (PCH) and a downlink-shared channel (DL-SCH), an uplink scheduling grant, and HARQ information. Paging channel (PCH) and downlink-shared channel (DL-SCH) are transmitted through PDSCH. Accordingly, the base station and the terminal generally transmit and receive data through the PDSCH except for specific control information or specific service data.

Data of the PDSCH is transmitted to which UE (one or a plurality of UEs), and information on how the UEs should receive and decode the PDSCH data is included in the PDCCH and transmitted. For example, a specific PDCCH is CRC masked with a Radio Network Temporary Identity (RNTI) of "A", a radio resource (eg, frequency location) of "B" and a transmission type information of "C" (eg, It is assumed that information on data transmitted using a transport block size, modulation scheme, coding information, etc.) is transmitted through a specific subframe. In this case, the terminal in the cell monitors the PDCCH using the RNTI information it has, and if there is at least one terminal having an "A" RNTI, the terminals receive the PDCCH, and through the information of the received PDCCH " Receive the PDSCH indicated by B " and " C ".

6 shows a resource unit used to configure a control channel. In particular, FIG. 6A illustrates a case where the number of transmit antennas of a base station is one or two, and FIG. 6B illustrates a case where the number of transmit antennas of a base station is four. Only the RS (Reference Signal) pattern is different according to the number of transmitting antennas, and the method of setting a resource unit associated with the control channel is the same.

Referring to FIG. 6, the basic resource unit of the control channel is REG. The REG is composed of four neighboring resource elements (REs) in the state excluding the RS. REG is shown in bold in the figures. PCFICH and PHICH include 4 REGs and 3 REGs, respectively. The PDCCH is composed of CCE (Control Channel Elements) units, and one CCE includes nine REGs.

The UE is configured to check M ^(L) (≥ L) CCEs arranged in a continuous or specific rule in order to confirm whether a PDCCH composed of L CCEs is transmitted to the UE. There may be a plurality of L values to be considered by the UE for PDCCH reception. The CCE sets that the UE needs to check for PDCCH reception are called a search space. For example, the LTE system defines a search area as shown in Table 1.

Table 1

Here, the CCE aggregation level L represents the number of CCEs constituting the PDCCH, S _k ^(L) represents a search region of the CCE aggregation level L, and M ^(L) represents a candidate PDCCH to be monitored in the search region of the aggregation level L. Is the number of.

The search area may be divided into a UE-specific search space that allows access to only a specific terminal and a common search space that allows access to all terminals in a cell. The UE monitors a common search region with CCE aggregation levels of 4 and 8, and monitors a UE-specific search region with CCE aggregation levels of 1, 2, 4, and 8. The common search area and the terminal specific search area may overlap.

In addition, the position of the first (with the smallest index) CCE in the PDCCH search region given to any UE for each CCE aggregation level value is changed every subframe according to the UE. This is called PDCCH search region hashing.

7 shows an example of distributing CCEs in a system band. Referring to FIG. 7, a plurality of logically continuous CCEs are input to an interleaver. The interleaver performs a function of mixing input CCEs in REG units. Therefore, frequency / time resources constituting one CCE are physically dispersed in the entire frequency / time domain in the control region of the subframe. As a result, the control channel is configured in units of CCE, but interleaving is performed in units of REGs, thereby maximizing frequency diversity and interference randomization gain.

Hereinafter, machine type communication (MTC) will be described.

MTC means communication between a machine and a machine without human intervention, and the terminal used for the MTC is an MTC device. MTC is also called M2M (Machine to Machine). The services provided through the MTC are different from those in the existing human communication, and there are various categories of services as follows. For example, services such as tracking, metering, payment systems, healthcare services, remote control, and the like are provided by the MTC.

8 is a view for explaining the structure of the machine type communication (MTC).

The MTC terminal communicates with another MTC terminal or MTC server through a mobile communication network. As illustrated in FIG. 8, the MTC server may provide the MTC user with metering, road information, water level measurement, utilization of a surveillance camera, inventory reporting of a vending machine, adjustment of a user electronic device, and the like, which are services provided through an MTC terminal. .

In order to efficiently support the MTC service, characteristics such as low mobility, time tolerant or delay tolerant, delay tolerance, and small data transmission of the MTC terminal may be considered. . For this reason, the MTC terminal may be referred to as a delay tolerant access support terminal.

In case of MTC service, since the amount of transmission data is small and the number of MTC terminals operating in one cell is large, the scheduling of each MTC terminal for uplink / downlink data transmission at each moment becomes very burdensome for the base station or eNB. . Accordingly, a method of reducing the control channel overhead burden may be considered by grouping a plurality of MTC terminals and performing uplink / downlink scheduling in units of such MTC groups. However, scheduling in a group unit applies the same control information to a plurality of MTC terminals, thereby limiting scheduling flexibility. In addition, if the scheduling of the MTC group is not performed, control information for a plurality of MTC devices should be transmitted to a limited control region, for example, a PDCCH region, which may cause a shortage of PDCCH capacity.

Meanwhile, in the case of the relay node proposed in the LTE-A system, the discovery region is set in the PDSCH region through the higher layer signaling due to the capacity shortage problem of the PDCCH. There is a problem that the area does not reflect mobility.

Accordingly, the present invention is to propose a method that can flexibly cope with the mobility of the MTC terminal without causing a lack of PDCCH capacity.

First, in the present invention, a plurality of MTC terminals, for example, 100 to 1000 MTC terminals are divided into one MTC group, each MTC terminal group specific PDCCH is placed in a PDSCH region, and the position of the PDSCH region is grouped. A method of indicating using a PDCCH masked with -RNTI may be considered. Here, the PDCCH masked with the group-RNTI is obtained through blind decoding in a search region configured in the conventional PDCCH region. In addition, the MTC UE group specific PDCCH located in the PDSCH region may be referred to as an E-PDCCH (Enhanced-PDCCH).

 Therefore, since the MTC terminal can know in advance the group-RNTI of the group to which it belongs (which can be obtained through system information or a random access procedure), the MTC terminal group specific PDCCH is determined in the conventional PDCCH region using the corresponding group-RNTI. Decode and use this to determine the location of an E-PDCCH (Enhanced-PDCCH) region. Here, the E-PDCCH region means the E-PDCCH search region of the MTC group including the MTC terminal.

According to this method, the E-PDCCH search region can be varied by differently setting the value of the group PDCCH transmitted through the existing PDCCH region (that is, the control information transmitted through the group PDCCH). Can be sent to. That is, it may support dynamic configuration of the search area, and may work advantageously when the MTC terminal (or relay node) has mobility.

Or, in the case of the MTC terminal, if there is almost no change in the group configuration and its members, since once configured MTC group will not change for a long time, the position of the E-PDCCH of each MTC terminal in the MTC group in advance RRC Informed signaling may also be considered. Accordingly, the position indicated by the group PDCCH is configured to be a logical or physical (starting) position of the E-PDCCHs for the plurality of MTC terminals, and a few E-PDCCHs among the E-PDCCHs for the plurality of MTC terminals are themselves. By signaling that the scheduling information of through an upper layer signal such as an RRC signal, it can be implemented without separate blind decoding for its E-PDCCH in the E-PDCCH region. Of course, a method of signaling candidate sets that may be its own E-PDCCH in the E-PDCCH region is also possible.

In addition, PDCCH search region hashing may be equally applied to the E-PDCCH region. For example, the position of the first (smallest index) resource allocated to the MTC group in the E-PDCCH region, that is, the search region of the E-PDCCH may change every subframe according to the MTC group identifier.

9 is a flowchart illustrating a method of receiving control information by an MTC terminal according to an embodiment of the present invention.

Referring to FIG. 9, the MTC terminal first performs blind decoding on a search region configured in a conventional PDCCH region as in step 901 to obtain a PDCCH masked with a group-RNTI. Here, the PDCCH masked with the group-RNTI may signal the location of the search region for the E-PDCCH configured in the PDSCH region as described above, or may signal the location itself of the E-PDCCH for only one MTC terminal. It may be. Hereinafter, for convenience of description, it is assumed that the location of the search region for the E-PDCCH is signaled.

Subsequently, in step 902, the MTC terminal may blindly decode the search region for the E-PDCCH to obtain E-PDCCHs of the MTC group to which the MTC terminal belongs. As described above, since the location of the E-PDCCH of each MTC terminal in the MTC group may be defined in advance through a higher layer, the MTC terminal determines which of the E-PDCCHs acquired in step 902 is its E-PDCCH. Able to know.

Finally, in step 903, the MTC terminal performs uplink signal transmission and downlink signal reception according to scheduling information included in its E-PDCCH, that is, resource allocation information.

Meanwhile, a method of reducing the size of the E-PDCCH itself may also be considered. For example, if resource allocation (for downlink signal reception or uplink signal transmission) of grouped MTC terminals is performed in a specific pattern, the bit size of resource allocation information included in the E-PDCCH may be reduced. For example, if you allocate a resource for every MTC only in a specified size unit (such as 1 RB or 1 subcarrier) or an integer multiple of it and configure it as a continuous index, it will tell you the location of the first resource region and only signal the offset value from it. In this way, the bit size of the resource allocation information can be significantly reduced. Alternatively, if only one RB is continuously allocated to all MTC terminals, each MTC terminal may recognize only the location in its own group and recognize the location of resources scheduled to it without additional resource allocation information. In addition, since the MCS of each of the MTC terminals included in the MTC group has a high probability of being a fixed value, the MCS value transmitted through the E-PDCCH may be omitted. Therefore, the E-PDCCH for the MTC group according to the present invention can be designed to be much smaller than the size of the R-PDCCH for the relay node, a number of E-PDCCH can be multiplexed in one RB. Or it may be configured as a PUCCH format (PUCCH format 3 of the LTE-A system) for transmitting uplink feedback information for a plurality of carriers at once.

In the above, it is assumed that only a case in which a plurality of MTC terminals are included in the MTC group, but it is obvious to those skilled in the art that the case in which the MTC group is composed of one MTC terminal is not excluded.

10 is a diagram for one example of mapping an E-PDCCH for an MTC terminal according to an embodiment of the present invention.

Referring to FIG. 10, the UE performs blind decoding on a search region configured in a conventional PDCCH region to obtain a PDCCH 1001 masked with a group-RNTI. In FIG. 10, for convenience of description, it is assumed that the location 1002 of the search region for the E-PDCCH is signaled. Of course, the position of the first resource (with the smallest index) of the search region 1002 of the E-PDCCH may change every subframe according to the MTC group identifier.

The MTC terminal may blindly decode the search region 1002 for the E-PDCCH to obtain the E-PDCCHs 1003 of the MTC group to which the MTC terminal belongs. As described above, since the location of the E-PDCCH of each MTC terminal in the MTC group may be defined in advance through an upper layer, the MTC terminal may know which of its E-PDCCHs is the E-PDCCH in the E-PDCCHs 1003. have.

11 illustrates a block diagram of a communication device according to an embodiment of the present invention.

Referring to FIG. 11, the communication device 1100 includes a processor 1110, a memory 1120, an RF module 1130, a display module 1140, and a user interface module 1150.

The communication device 1100 is illustrated for convenience of description and some modules may be omitted. In addition, the communication device 1100 may further include necessary modules. In addition, some modules in the communication device 1100 may be classified into more granular modules. The processor 1110 is configured to perform an operation according to the embodiment of the present invention illustrated with reference to the drawings. In detail, the detailed operation of the processor 1110 may refer to the contents described with reference to FIGS. 1 to 10.

The memory 1120 is connected to the processor 1110 and stores an operating system, an application, program code, data, and the like. The RF module 1130 is connected to the processor 1110 and performs a function of converting a baseband signal into a radio signal or converting a radio signal into a baseband signal. To this end, the RF module 1130 performs analog conversion, amplification, filtering and frequency up-conversion, or a reverse process thereof. The display module 1140 is connected to the processor 1110 and displays various information. The display module 1140 may use well-known elements such as, but not limited to, a liquid crystal display (LCD), a light emitting diode (LED), and an organic light emitting diode (OLED). The user interface module 1150 is connected to the processor 1110 and may be configured with a combination of well-known user interfaces such as a keypad and a touch screen.

The embodiments described above are 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 of the components and / or features to form an embodiment of the invention. The order of the operations described in the embodiments of the present invention may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment. It is obvious that the claims may be combined to form an embodiment by combining claims that do not have an explicit citation relationship in the claims or as new claims by post-application correction.

In this document, embodiments of the present invention have been mainly described based on data transmission / reception relations between a terminal and a base station. Certain operations described in this document as being performed by a base station may in some cases be performed by an upper node thereof. That is, it is apparent that various operations performed for communication with a terminal in a network including a plurality of network nodes including a base station may be performed by the base station or network nodes other than the base station. A base station may be replaced by terms such as a fixed station, a Node B, an eNode B (eNB), an access point, and the like.

Embodiments 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 application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), FPGAs ( field programmable gate arrays), 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 a module, procedure, function, etc. that performs the functions or operations described above. The 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 will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit of the invention. Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

In the above-described wireless communication system, the method for setting a search area of the MTC terminal and an apparatus therefor have been described with reference to the example applied to the 3GPP LTE system. However, the present invention can be applied to various wireless communication systems in addition to the 3GPP LTE system.

Claims (10)

1. A method for receiving downlink control information by a terminal in a wireless communication system,

   Receiving control information masked with an identifier of a group to which the terminal belongs in the first region of the subframe;

   Setting a group specific search region of a group to which the terminal belongs in the second region of the subframe according to the first control information; And

   Receiving, in the group specific search region, group specific downlink control information of a group to which the terminal belongs;

   The group specific downlink control information,

   Characterized in that the resource allocation information for each of the terminals belonging to the group,

   Receiving downlink control information.
2. The method of claim 1,

   The first control information,

   Including information about a starting point of the group specific search area,

   The starting point is,

   Characterized in accordance with the predefined rule for each subframe based on the identifier of the group to which the terminal belongs,

   Receiving downlink control information.
3. The method of claim 1,

   Receiving the index of the terminal in the group through a higher layer,

   The group specific downlink control information,

   The resource allocation information for each of the terminals belonging to the group, characterized in that configured in the terminal index order,

   Receiving downlink control information.
4. The method of claim 1,

   Resources for each of the terminals belonging to the group,

   Characterized in that it is constantly assigned to a predetermined size unit,

   Receiving downlink control information.
5. The method of claim 1,

   The first region,

   A control region of the subframe,

   The second area is,

   Characterized in that the data area of the subframe,

   Receiving downlink control information.
6. A terminal device in a wireless communication system,

   In a first area of the subframe, a wireless communication module for receiving control information masked with the identifier of the group to which the terminal device belongs; And

   A processor for setting a group specific search region of a group to which the terminal apparatus belongs in a second region of the subframe according to the first control information,

   The processor,

   Obtaining group specific downlink control information of a group to which the terminal device belongs in the group specific search region,

   The group specific downlink control information,

   Characterized in that the resource allocation information for each of the terminal devices belonging to the group,

   Terminal device.
7. The method of claim 6,

   The first control information,

   Including information about a starting point of the group specific search area,

   The starting point is,

   Characterized in accordance with the predefined rule for each subframe based on the identifier of the group to which the terminal device belongs,

   Terminal device.
8. The method of claim 6,

   The receiving module,

   Receive an index of the terminal device in the group through a higher layer,

   The group specific downlink control information,

   The resource allocation information for each of the terminal devices belonging to the group is configured in the order of the terminal index,

   Terminal device.
9. The method of claim 6,

   Resources for each of the terminal devices belonging to the group,

   Characterized in that it is constantly assigned to a predetermined size unit,

   Terminal device.
10. The method of claim 6,

    The first region,

    A control region of the subframe,

    The second area is,

    Characterized in that the data area of the subframe,

    Terminal device.

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