KR20150037461A - Methods for Transmitting and Receiving Downlink Data Channels and Apparatuses thereof - Google Patents

Abstract

The present invention relates to a method and apparatus for transmitting / receiving a downlink data channel, and a method for transmitting a PDCCH or an EPDCCH including PDSCH scheduling information for a UE and the PDSCH according to an embodiment of the present invention, Repeatedly transmitting the PDCCH or the EPDCCH through N downlink subframes, and repeatedly transmitting the PDSCH through P downlink subframes, wherein the PDCCH or the EPDCCH is repeatedly transmitted When the link subframe index is M, the downlink subframe index at which the PDSCH repeated transmission starts is M + k.

Description

[0001] The present invention relates to a method and apparatus for transmitting and receiving downlink data channels,

The present invention relates to a method and apparatus for transmitting and receiving a downlink data channel, and more particularly, to a method and apparatus for transmitting a downlink data channel for a MTC (Machine Type Communication) terminal.

Machine Type Communication (MTC) or Machine to Machine (M2M) is the communication that takes place between a device and an object with no human intervention or minimal intervention. A "machine" may refer to an entity that does not require direct manipulation or intervention by a person, and an "MTC" may refer to a form of data communication that includes one or more of these "machines". Examples of the "machine" include a smart meter equipped with a mobile communication module, a vending machine, and the like. In recent years, a smart phone Mobile terminals with MTC function are considered as a form of "machine".

The MTC terminal can be installed in a place where the radio wave environment is worse than that of a general terminal. Therefore, the coverage of the MTC terminal should be improved to 20 dB or more in comparison with the coverage of the general terminal.

In order for the MTC terminal to operate at 20 dB or more improved coverage as compared with a general terminal, it is necessary to repeatedly transmit control information and / or data of each physical channel transmitted only in one subframe in a plurality of subframes. In addition, when another LTE / LTE-Advanced terminal and the MTC terminal overlap the common search space, there is a possibility that an error occurs in the MTC terminal checking the control information. Therefore, it is necessary to transmit control information and data of the physical channel in accordance with the characteristics of the MTC terminal.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus for transmitting and receiving a downlink data channel for an MTC terminal in order to overcome the above-described problems.

According to an aspect of the present invention, there is provided a method for transmitting a PDCCH or an EPDCCH including PDSCH scheduling information for a UE and a PDSCH according to an embodiment of the present invention includes transmitting the PDCCH or the EPDCCH to N DL sub- And repeatedly transmitting the PDSCH through the P number of downlink subframes. When the downlink subframe index at which the repeated transmission of the PDCCH or the EPDCCH ends is M, the PDSCH And the downlink subframe index at which the repeated transmission starts is M + k.

A method for receiving a PDCCH or EPDCCH including PDSCH scheduling information and a corresponding PDSCH from a base station according to another embodiment of the present invention includes repeatedly receiving the PDCCH or the EPDCCH through N downlink subframes, And repeatedly receiving the PDSCH through the P number of downlink subframes. When the downlink subframe index of the PDCCH or the repeated reception of the EPDCCH ends is M, the downlink sub- And the frame index is M + k.

The PDCCH or the EPDCCH including the PDSCH scheduling information for the UE according to another embodiment of the present invention and the base station transmitting the PDSCH repeatedly transmits the PDCCH or the EPDCCH through the N downlink subframes, And a downlink subframe index in which the repeated transmission of the PDCCH or the EPDCCH is ended is M, the downlink subframe index at which the PDSCH repeated transmission starts is M + k of the transmitting unit.

The PDCCH or EPDCCH including the PDSCH scheduling information from the BS according to another embodiment of the present invention and the UE receiving the PDSCH repeatedly receive the PDCCH or the EPDCCH through N downlink subframes, And a DL subframe index in which the repeated reception of the PDCCH or the EPDCCH is ended is M, the DL subframe index in which the PDSCH repeated reception starts is M + k of the reception unit.

In implementing the present invention, a method and apparatus for transmitting and receiving a downlink data channel for the MTC terminal can be implemented.

1 shows an example of a wireless communication system to which an embodiment of the present invention is applied.
2 is a diagram showing an example of blind decoding PDCCH / EPDCCH and acquiring PDSCH scheduling information.
FIG. 3 is a diagram showing four PDCCH formats.
4 is a diagram showing the number of EREGs per ECCE.
Figure 5 is a diagram of the supported EPDCCH format.
6 is a diagram for transmitting a PDSCH after repeated transmission of a PDCCH / EPDCCH according to an embodiment of the present invention.
FIG. 7 is a diagram illustrating an example in which the number of PRBs, the number of repetitions, and the MCS are set according to the PDSCH format according to an exemplary embodiment of the present invention.
8 is a diagram illustrating repetitive transmission of a PDCCH or EPDCCH including PDSCH scheduling information according to an embodiment of the present invention, and transmission of the PDSCH according to the repetitive transmission.
9 is a diagram illustrating a process in which a base station repeatedly transmits a PDCCH or EPDCCH to a UE according to an embodiment of the present invention.
10 is a diagram illustrating a process of repeatedly receiving PDCCH or EPDCCH from a base station according to an embodiment of the present invention.
11 is a diagram illustrating a configuration of a base station according to another embodiment of the present invention.
12 is a diagram illustrating a configuration of a user terminal according to another embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference numerals even though they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 shows an example of a wireless communication system to which an embodiment of the present invention is applied.

The wireless communication system in the present invention is widely deployed to provide various communication services such as voice, packet data and the like. A wireless communication system includes a user equipment (UE) and a base station (BS, or eNB). The user terminal in this specification is a comprehensive concept of a terminal in wireless communication. It is a comprehensive concept which means a mobile station (MS), a user terminal (UT), an SS (User Equipment) (Subscriber Station), a wireless device, and the like.

A base station 20 or a cell generally refers to a station that communicates with a user terminal and includes a Node-B, an evolved Node-B (eNB), a sector, a Site, , A Base Transceiver System (BTS), an Access Point, a Relay Node, a Remote Radio Head (RRH), a Radio Unit (RU), and a small cell.

That is, in the present specification, the base station 20 or the cell represents a part or function covered by BSC (Base Station Controller) in CDMA, Node-B in WCDMA, eNB in LTE or sector (site) It is meant to cover a variety of coverage areas such as megacels, macrocells, microcells, picocells, femtocells and relay nodes, RRH, RU, and small cell coverage.

Since the various cells listed above exist in the base station controlling each cell, the base station can be interpreted into two meanings. i) a device itself providing a megacell, a macrocell, a microcell, a picocell, a femtocell, or a small cell in relation to a wireless region, or ii) the wireless region itself. i indicate to the base station all devices that are controlled by the same entity or that interact to configure the wireless region as a collaboration. An eNB, an RRH, an antenna, an RU, an LPN, a point, a transmission / reception point, a transmission point, a reception point, and the like are exemplary embodiments of a base station according to a configuration method of a radio area. ii) may indicate to the base station the wireless region itself that is to receive or transmit signals from the perspective of the user terminal or from a neighboring base station.

Therefore, a base station is collectively referred to as a megacell, a macrocell, a microcell, a picocell, a femtocell, a small cell, an RRH, an antenna, an RU, a low power node (LPN), a point, an eNB, Quot;

Herein, the user terminal and the base station are used in a broad sense as the two transmitting and receiving subjects used to implement the technical or technical idea described in this specification, and are not limited by a specific term or word. The user terminal and the base station are used in a broad sense as two (uplink or downlink) transmitting and receiving subjects used to implement the technology or technical idea described in the present invention, and are not limited by a specific term or word. Here, an uplink (UL, or uplink) means a method of transmitting / receiving data to / from a base station by a user terminal, and a downlink (DL or downlink) .

There are no restrictions on multiple access schemes applied to wireless communication systems. Various multiple access schemes such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), OFDM-FDMA, OFDM- Can be used. An embodiment of the present invention can be applied to asynchronous wireless communication that evolves into LTE and LTE-Advanced via GSM, WCDMA, and HSPA, and synchronous wireless communication that evolves into CDMA, CDMA-2000, and UMB. The present invention should not be construed as limited to or limited to a specific wireless communication field and should be construed as including all technical fields to which the idea of the present invention can be applied.

A TDD (Time Division Duplex) scheme in which uplink and downlink transmissions are transmitted using different time periods, or an FDD (Frequency Division Duplex) scheme in which they are transmitted using different frequencies can be used.

In systems such as LTE and LTE-Advanced, the uplink and downlink are configured on the basis of one carrier or carrier pair to form a standard. The uplink and the downlink are divided into a Physical Downlink Control Channel (PDCCH), a Physical Control Format Indicator CHannel (PCFICH), a Physical Hybrid ARQ Indicator CHannel, a Physical Uplink Control CHannel (PUCCH), an Enhanced Physical Downlink Control Channel (EPDCCH) Transmits control information through the same control channel, and is configured with data channels such as PDSCH (Physical Downlink Shared CHannel) and PUSCH (Physical Uplink Shared CHannel), and transmits data.

On the other hand, control information can also be transmitted using EPDCCH (enhanced PDCCH or extended PDCCH).

In this specification, a cell refers to a component carrier having a coverage of a signal transmitted from a transmission point or a transmission point or transmission / reception point of a signal transmitted from a transmission / reception point, and a transmission / reception point itself .

The wireless communication system to which the embodiments are applied may be a coordinated multi-point transmission / reception system (CoMP system) or a coordinated multi-point transmission / reception system in which two or more transmission / reception points cooperatively transmit signals. antenna transmission system, or a cooperative multi-cell communication system. A CoMP system may include at least two multipoint transmit and receive points and terminals.

The multi-point transmission / reception point includes a base station or a macro cell (hereinafter referred to as 'eNB'), and at least one mobile station having a high transmission power or a low transmission power in a macro cell area, Lt; / RTI >

Hereinafter, a downlink refers to a communication or communication path from a multipoint transmission / reception point to a terminal, and an uplink refers to a communication or communication path from a terminal to a multiple transmission / reception point. In the downlink, a transmitter may be a part of a multipoint transmission / reception point, and a receiver may be a part of a terminal. In the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of multiple transmission / reception points.

Hereinafter, a situation in which a signal is transmitted / received through a channel such as PUCCH, PUSCH, PDCCH, EPDCCH, and PDSCH is expressed as 'PUCCH, PUSCH, PDCCH, EPDCCH and PDSCH are transmitted and received'.

In the following description, the description that transmits (transmits) or receives (PDCCH) or transmits or receives a signal via the PDCCH can be used to mean transmitting or receiving the EPDCCH or transmitting (transmitting) or receiving the signal via the EPDCCH.

That is, the physical downlink control channel described below may mean a PDCCH, an EPDCCH, or a PDCCH and an EPDCCH.

Also, for convenience of description, EPDCCH, which is an embodiment of the present invention, may be applied to the portion described with PDCCH, and EPDCCH may be applied to the portion described with EPDCCH according to an embodiment of the present invention.

Meanwhile, the High Layer Signaling described below includes RRC signaling for transmitting RRC information including RRC parameters.

The base station or the eNB 20 performs downlink transmission to the terminals. The eNB includes a physical downlink shared channel (PDSCH) as a main physical channel for unicast transmission, downlink control information such as scheduling required for reception of PDSCH, and uplink data channel A physical downlink control channel (PDCCH) for transmitting scheduling grant information for transmission in a Physical Uplink Shared Channel (PUSCH). Hereinafter, the transmission / reception of a signal through each channel will be described in a form in which the corresponding channel is transmitted / received.

Referring to FIG. 1, a BS 20 transmits downlink control information (DCI) to a UE 10 through a PDCCH / EPDCCH. The DCI may include a downlink scheduling assignment including PDSCH resource information, or may include an uplink scheduling grant including PUSCH resource information.

That is, the base station 20 uses the DCI to allocate upstream / downstream data transmission resources to the terminal 10, and transmits the DCI to the terminal 10 using the downlink control channel. The DL control channel can be classified into a PDCCH and an EPDCCH according to the location of a transmission resource used for transmitting the DCI.

The PDCCH is transmitted in a control area set through CFI (Control Format Indicator). The control region is formed over the entire downlink bandwidth and is composed of one to four OFDM symbols according to the CFI setting value for each subframe.

The EPDCCH is transmitted using the remaining transmission resources except for the control region in each subframe. A transmission resource used for EPDCCH transmission is divided into a plurality of predefined physical resource block pairs (PRBs) and predefined subframes by higher layer signaling (e.g., RRC (Radio Resource Control) Can only be used.

When a DCI is transmitted through a PDCCH, a unit of a transmission resource as a base may be referred to as a CCE (Control Channel Element). One CCE may be composed of nine REGs (Resource Element Groups), and one REG may be composed of four REs (Resource Elements).

When the DCI is transmitted through the EPDCCH, the unit of the transmission resource as the basic unit can be referred to as ECCE (Enhanced CCE). One ECCE is composed of four or eight EREGs (Enhanced REG) according to cyclic prefix length and / or TDD configuration, and one EREG is variable according to RE used for RS (Reference Signal) transmission And a plurality of REs.

The base station 20 can set the number of CCEs used when transmitting one DCI on the PDCCH according to the channel condition of the UE. This is referred to as an aggregation level, and 1, 2, 4, or 8 CCEs can be used depending on the channel condition of the UE.

In addition, the base station 20 can set the number of ECCEs used when transmitting one DCI through the EPDCCH according to the channel condition of the terminal. This is called an aggregation level, and 1, 2, 4, 8, 16 or 32 ECCEs can be used depending on the channel condition of the UE.

As described above, the PDCCH / EPDCCH is composed of a plurality of CCE / ECCEs, and the base station can transmit a plurality of DCIs to each terminal in each subframe. At this time, the CCE / ECCE allocation information (i.e., the CCE combining level information used for one DCI transmission and the location information of the CCE transmission resource) necessary for the UE to receive the DCI through the PDCCH / EPDCCH is separately provided to the UE Therefore, the UE performs blind decoding on a CCE / ECCE transmission resource and a possible combining level to confirm the DCI transmitted to the UE.

Since the UE can not practically perform blind decoding of all possible CCE / ECCE combinations for each CCE / ECCE existing in the PDCCH / EPDCCH by considering the processing delay, Blind decoding is performed only for a candidate / EPDCCH candidate. The CCE index / ECCE index constituting the PDCCH candidate / EPDCCH candidate for each combining level can be defined as a function of a combining level, a value of an RNTI (Radio Network Temporary Identifier), and a slot number (or a subframe number). The UE can perform blind decoding for only a limited number of PDCCH candidates / EPDCCH candidates per combining level every subframe.

As an example, FIG. 2 shows a method in which a general terminal performs blind decoding of a PDCCH / EPDCCH and receives a PDSCH. Referring to FIG. 2, the UE attempts blind decoding of the PDCCH / EPDCCH with respect to the PDCCH candidate / EPDCCH candidate. The DCI has a CRC (Cyclic Redundancy Check) added thereto, and the UE checks the CRC to check the DCI transmitted to the UE. When the UE confirms the DCI transmitted to the UE as a result of the CRC check, the UE acquires the downlink scheduling information included in the DCI and decodes the PDSCH using the downlink data transmission resource in the same subframe as the subframe in which the DCI is transmitted do.

Figure 2 illustrates the blind decoding of the PDCCH / EPDCCH and obtaining PDSCH scheduling information. In a similar manner to FIG. 2, the PUSCH scheduling information may also be obtained by blind decoding the PDCCH / EPDCCH.

In the conventional 3GPP LTE / LTE-Advanced system, a newly defined EPDCCH is used in a PDCCH and a Rel-11 system defined in a Rel-10 or lower system as a downlink control information (DCI) transmission channel for a terminal .

FIG. 3 is a diagram showing four PDCCH formats. PDCCH is transmitted using the four PDCCH formats shown in FIG. 3 for link adaptation according to the downlink radio channel quality of the UE and the size of the DCI. In FIG. 4, the number of CCEs (Number of CCEs) indicates an aggregation level.

4 is a diagram showing the number of EREGs per ECCE. 4,

The value of the number of EREGs per ECCE is determined according to the characteristics of the subframe. In the case of the normal cyclic prefix, the value of the normal subframe or the special subframe of 3, 4, 8 Special subframe, configuration 3, 4, 8). In the case of an extended cyclic prefix, a normal subframe or special subframes 1, 2, 3, 5 and 6 of 1, 2, 3, ).

5 is a diagram for supported EPDCCH formats. In FIG. 5, case A and case B are divided into five types according to localized transmission and distributed transmission, respectively.

That is, in the case of the EPDCCH, five EPDCCH formats are also transmitted according to FIGS. 4 and 5 for link adaptation for DCI transmission.

In a conventional LTE / LTE-Advanced system, a PDCCH / EPDCCH including one downlink DCI for PDSCH resource allocation for an arbitrary terminal is transmitted through one downlink subframe. Also, regardless of the PDCCH / EPDCCH format, the DL sub-frame in which transmission is performed for the DL-allocated PDCCH or EPDCCH including the PDSCH resource allocation information is the same as the sub-frame in which the PDSCH transmission is performed. That is, it is defined that the PDSCH is transmitted according to the DL allocation information in a DL sub-frame in which DL allocation DCI transmission for an arbitrary UE is performed.

[ LTE  Low-cost based MTC ]

As the LTE network spreads, mobile operators want to minimize the number of Radio Access Terminals (RATs) to reduce network maintenance costs. However, conventional MTC products based on a GSM / GPRS network are increasing, and MTC using a low data rate can be provided at low cost. Therefore, there is a problem in that two RATs must be operated respectively, since LTE network is used for general data transmission and GSM / GPRS network is used for MTC. Therefore, Of the total revenue.

In order to solve such a problem, a cheap MTC terminal using a GSM / EGPRS network should be replaced with an MTC terminal using an LTE network, and various requirements for lowering the price of an LTE MTC terminal are suggested for this purpose.

To support the low-cost LTE MTC terminal, a technique such as a narrow band support / single RF chain / half duplex FDD / long DRX (Long Discontinued Reception) is exemplified. However, the above methods, which are considered for lowering the price, can reduce the performance of the MTC terminal as compared with the conventional LTE terminal.

In addition, about 20% of MTC terminals supporting MTC services such as smart metering are installed in a 'Deep indoor' environment such as a basement, so that for successful MTC data transmission, It should be improved by about 20dB compared with the coverage of the terminal. In addition, considering the performance reduction due to the above-mentioned specification change, the coverage of the LTE MTC terminal should be improved by 20 dB or more.

Various methods for robust transmission such as PSD boosting or low coding rate and time domain repetition in order to improve the coverage while lowering the LTE MTC terminal price Are considered for each physical channel.

The requirements of low-cost MTC terminal based on LTE are as follows.

1) The data transmission rate must satisfy the data transmission rate provided by the minimum EGPRS-based MTC terminal, that is, the downlink 118.4kbps and the uplink 59.2kbps.

2) Frequency efficiency should be improved dramatically compared to GSM / EGPRS MTC terminal.

3) The service area provided shall not be less than that provided by the GSM / EGPRS MTC terminal.

4) Power consumption should not be larger than GSM / EGPRS MTC terminal.

5) Legacy LTE terminal and LTE MTC terminal should be available at the same frequency.

6) Reuse the existing LTE / SAE network.

7) Optimization is performed not only in FDD mode but also in TDD mode.

8) Low-cost LTE MTC terminals must support limited mobility and low power consumption modules.

In order to support 20dB improved coverage compared to an extended general LTE terminal, the MTC terminal repetitively transmits a PDCCH or EPDCCH transmission, which has been performed in units of one downlink subframe, through a plurality of downlink subframes, The MTC terminal also needs to perform decoding by combining the PDCCH or EPDCCH received through the plurality of downlink subframes. In this case, when the DL-allocated DCI is transmitted through the corresponding PDCCH or EPDCCH, the DL-allocated DCI based on the same downlink subframe in the existing LTE / LTE-Advanced terminal and the PDSCH transmission / A new definition of the repetition PDCCH and EPDCCH transmission / reception and thus the PDSCH transmission / reception timing relationship is needed.

The present invention proposes a PDCCH or EPDCCH transmission format for a MTC terminal and a corresponding PDSCH transmission scheme.

In particular, we define a new PDCCH / EPDCCH format for DCI (Downlink Control Information) transmission for MTC terminals, and propose a PDSCH transmission method based on this.

The present invention proposes a PDCCH / EPDCCH transmission method for DL allocation DCI transmission including PDSCH scheduling information in a base station for a MTC terminal, a PDSCH transmission method based on the PDCCH / EPDCCH transmission method, and a PDCCH / EPDCCH and PDSCH reception method of the MTC terminal based thereon .

In particular, the relationship between the PDCCH / EPDCCH transmission downlink subframe including the DL allocation and the PDSCH transmission downlink subframe accordingly is defined. In particular, we propose a method to define PDSCH transmission subframe and PDSCH repeat count for MTC terminal.

As described above, the PDCCH or EPDCCH including one DCI for an arbitrary terminal in a conventional LTE / LTE-Advanced system is transmitted through one downlink subframe. For example, PDCCH / EPDCCH including DL allocation DCI, which is PDSCH resource allocation information for an arbitrary LTE / LTE-Advanced terminal, or PDCCH / EPDCCH including UL grant DCI, which is PUSCH resource allocation information, One PDCCH or EPDCCH including one DCI for one UE or a group of UEs is transmitted in one DL subframe. In particular, in the case of a DL-allocated PDCCH or EPDCCH for transmitting PDSCH resource allocation information, the corresponding PDSCH is transmitted in the same subframe as the DL-allocated PDCCH or EPDCCH-transmitted DL subframe. However, in the case of the MTC terminal as described above, the PDCCH or the EPDCCH including one DCI can be repeatedly transmitted through a plurality of downlink subframes to support enhanced coverage. In this case, when a PDCCH / EPDCCH for transmitting a DL-assigned DCI for an arbitrary MTC terminal is transmitted through arbitrary N downlink subframes, the DL subframe corresponding to the PDCCH / EPDCCH transmission and the PDSCH transmission It is necessary to define the relation with the downlink sub-frame.

Hereinafter, a PDCCH / EPDCCH transmission method for DL allocation DCI transmission that includes PDSCH scheduling information in a base station for a MTC terminal will be described. The relationship between a PDCCH / EPDCCH transmission downlink subframe including a DL allocation and a PDSCH transmission downlink subframe A method for transmitting and receiving a downlink data channel for a specified MTC terminal, and a device therefor will be described.

Method 1. PDSCH  The starting sub-frame ( PDSCH starting subframe )

When maintaining the timing relationship between the PDCCH / EPDCCH and the PDSCH in the existing LTE / LTE-Advanced system, the MTC terminal will transmit the entire bandwidth of the N downlink subframes in which the corresponding PDCCH / EPDCCH transmission is performed until decoding of the PDCCH / EPDCCH is completed The buffering of the PDSCH area of the PDSCH shall be performed. This may be inefficient in terms of the complexity of the MTC terminal. In order to solve this problem, in the present invention, when a DL subframe in which the last PDCCH / EPDCCH repetition is performed is referred to as a DL subframe #M, a corresponding PDSCH transmission start subframe is defined as a DL subframe # (M + k) do. However, the value of k may be limited to an integer of 0 or more.

6 is a diagram for transmitting a PDSCH after repeated transmission of a PDCCH / EPDCCH according to an embodiment of the present invention. PDCCH / EPDCCH and the PDSCH timing (k = 1). You can set the value of k as shown in the previous example to 1. That is, it is possible to define that the PDSCH is transmitted from the next subframe of the last transmission subframe of the repeated PDCCH or EPDCCH. That is, as shown in FIG. 6, the PDCCH or the EPDCCH including one DL-allocated DCI for an arbitrary MTC terminal is transmitted from the DL subframe # (M-N + 1) indicated by 611 to the DL subframe #M The PDSCH transmission corresponding to the corresponding DL allocation information is transmitted from the DL subframe # (M + 1) indicated by 621 to the DL subframe # (M + P) indicated by 629, Can be achieved. Here, P is the number of repetitive PDSCH transmissions for the MTC terminal.

6, PDCCH / EPDCCH (PDCCH / EPDCCH transmission) repeatedly transmitted in FIG. 6 correspond to 631, 632, ..., 639, and they are repeated N times (Number of repetitions = N). The subframe number of the subframe 619 for which transmission has been completed is #M, and then the PDSCH is transmitted through the number of repetitions (P) of # (M + 1) transmission. The PDSCH that is repeated P times becomes 641, 642, ..., 649, respectively. "1" of M + 1 in the above shows a case where the timing k of the PDSCH is 1. As another embodiment for defining the k value, k = 4 can be fixed according to the timing relationship between the PDCCH / EPDCCH transmission including the existing UL grant (UL grant) and the PUSCH transmission. That is, it is possible to define that the PDSCH transmission starts from the 4th subframe after the last transmission subframe of the repeated PDCCH / EPDCCH.

Any integer that satisfies k ≥ 0 may be included in the scope of the present invention in addition to the specific example of the above k value.

Method 2. PDSCH  Repeat times ( Number of PDSCH repetition )

The P value is a function of the PDCCH / EPDCCH format including the function of the N value which is the repetition number of the DL-allocated PDCCH / EPDCCH containing the corresponding PDSCH allocation information or the P value of the PDSCH repetition number to be applied when transmitting the PDSCH according to the DL- Can be determined. As an example of this, the P value can be set in proportion to the N value. That is, it is possible to define that the relationship P = a · N is satisfied. Where a is an arbitrary positive constant.

For example, a = 1/2 can be defined. In this case, a repetition number of the PDSCH and a repetition number of the PDCCH / EPDCCH that transmits the PDSCH allocation information can be defined as half of the N value.

As another measure for determining the corresponding P value, it is possible to define any arbitrary plurality of PDSCH formats including the corresponding P value, and transmit the PDSCH format by including it in the DL allocation DCI. The PDSCH format may include PRB allocation information, MCS value, or the like, in addition to the PDSCH repetition number P value as shown in FIG. However, the number of PDSCH formats and the number of PRB allocations and repetitions per PDSCH format can be variously defined, and there is no limitation on these values.

FIG. 7 is a diagram illustrating a relationship in which a number of PRBs, a number of repetitions, and a Modulation and Coding Scheme (MCS) are set according to the PDSCH format according to an exemplary embodiment of the present invention. The respective values a, b, c, d, e, f, g, and h may be determined according to the embodiment. The MCS may be later determined according to the format of the PDSCH.

As another method of determining the number of PDSCH repetition times, it is possible to define a coverage level according to radio channel quality for each MTC terminal and to define a value of the PDSCH repetition number P for each coverage level. At this time, the coverage level for an arbitrary terminal may be set by the base station or may be implicitly set for each terminal through a PRACH procedure of the corresponding MTC terminal.

8 is a diagram illustrating repetitive transmission of a PDCCH or EPDCCH including PDSCH scheduling information according to an embodiment of the present invention, and transmission of the PDSCH according to the repetitive transmission.

The number N of repetitive transmissions in FIG. 8 is 5, and it is shown that a repetitive transmission (P = 2) of two PDSCHs is performed after one subframe (k = 1) after repeated transmission.

The base station 801 generates a downlink signal including a PDCCH or EPDCCH for the terminal 809 (S810). The generated downlink signal is transmitted in the first downlink subframe (S815). This is the first transmission during the repetitive transmission, and the terminal 809 receives the PDCCH or EPDCCH of the downlink signal (S819). The base station repeatedly generates and transmits a downlink signal including a PDCCH or EPDCCH for the UE 809. [ The base station generates a downlink signal including the PDCCH or the EPDCCH for the terminal 809 for the fifth iteration of the last iteration (S820). The generated downlink signal is transmitted in the fifth downlink subframe (S825). This is the fifth transmission during the repeated transmission, and the terminal 809 receives the PDCCH or the EPDCCH of the downlink signal (S829). When the iterative transmission is completed, the base station 801 transmits the PDCCH of the next subframe (since k = 1) of the fifth subframe in which iterative transmission is completed according to the PDSCH scheduling information included in the PDCCH or EPDCCH repeatedly transmitted in S815 to S825, PDSCH iterative transmission. The base station 801 generates a downlink signal including a PDSCH for the UE in step S830 and transmits the downlink signal in the sixth downlink subframe to the UE 809 in step S835. This is the first transmission of the PDSCH repeat transmission. The terminal receives the PDSCH of the downlink signal (S839). The base station 801 generates a downlink signal including the PDSCH for the UE in step S840 and transmits the downlink signal in the seventh downlink subframe to the UE 809 in step S845. This is the second transmission of the PDSCH repeat transmission. The terminal receives the PDSCH of the downlink signal (S849).

9 is a diagram illustrating a process in which a base station repeatedly transmits a PDCCH or EPDCCH to a UE according to an embodiment of the present invention. The base station transmits PDCCH or EPDCCH including the PDSCH scheduling information for the UE and the PDSCH according to the procedure of FIG.

The base station repeatedly transmits the PDCCH or the EPDCCH through N downlink subframes (S910). In step S920, the PDSCH is repeatedly transmitted through the P number of downlink subframes according to the scheduling information included in the repeatedly transmitted PDCCH or EPDCCH. Here, if the downlink subframe index on which the repeated transmission of the PDCCH or the EPDCCH is terminated is M, the downlink subframe index at which the PDSCH repeated transmission starts is M + k. That is, the PDSCH is transmitted in subframes after k in a subframe in which repeated transmission of PDCCH / EPDCCH is completed. The value of k may have an integer value of 0 or more, and in one embodiment, the value of k may be 1. Meanwhile, the UE receiving the repeated transmission may be a terminal supporting the MTC, and the value of P, which is a value for repetitive transmission of the PDSCH to be repeatedly transmitted, may have an integer value of 1 or more. In another embodiment, as described in method 2, the P value for repeated transmission of the PDSCH can be determined using the format of the PDCCH or the EPDCCH and the N value as shown in FIG. That is, the format and the value of N can be given as arguments of the function, and the base station and the UE can share information in the form of FIG.

10 is a diagram illustrating a process of repeatedly receiving PDCCH or EPDCCH from a base station according to an embodiment of the present invention. The UE receives PDCCH or EPDCCH including the PDSCH scheduling information and the PDSCH according to the process of FIG.

The UE repeatedly receives the PDCCH or the EPDCCH through N downlink subframes (S1010). In step S1020, the PDSCH is repeatedly received on the P downlink subframes according to the scheduling information included in the repeatedly received PDCCH or EPDCCH. Here, if the downlink subframe index on which the repeated reception of the PDCCH or the EPDCCH is terminated is M, the downlink subframe index at which the PDSCH repeated reception starts is M + k. That is, PDSCH is received in a subframe after k in a subframe in which repeated reception of PDCCH / EPDCCH is completed. The value of k may have an integer value of 0 or more, and in one embodiment, the value of k may be 1. Meanwhile, the UE may be a terminal supporting the MTC, and the value of P, which is a value for repetitive transmission of the PDSCH to be repeatedly received, may have an integer value of 1 or more. In another embodiment, as described in method 2, the P value for repeated PDSCH reception can be determined using the format of the PDCCH or EPDCCH and the N value as shown in FIG. That is, the format and the value of N can be given as arguments of the function, and the base station and the UE can share information in the form of FIG.

11 is a diagram illustrating a configuration of a base station according to another embodiment of the present invention.

11, a base station 1100 according to another embodiment includes a control unit 1110, a transmission unit 1120, and a reception unit 1130.

The controller 1110 is a PDCCH / EPDCCH transmission method for DL allocation DCI transmission including PDSCH scheduling information in the base station for the MTC terminal, which is required for performing the above-described present invention. The PDCCH / EPDCCH transmission downlink And controls the overall operation of the base station to perform the downlink data channel transmission / reception method for the MTC terminal in which the relationship between the subframe and the PDSCH transmission downlink subframe is specified.

The transmitting unit 1120 and the receiving unit 1130 are used to transmit and receive signals, messages, and data necessary for carrying out the present invention to and from the terminal.

In more detail, the base station of FIG. 11 transmits PDCCH or EPDCCH including PDSCH scheduling information for the UE and the PDSCH accordingly, and repeatedly transmits the PDCCH or EPDCCH. That is, the transmitter 1120 repeatedly transmits the PDCCH or the EPDCCH through N downlink subframes, repeatedly transmits the PDSCH through the P downlink subframes, and the controller 1110 transmits the PDCCH or the EPDCCH If the downlink subframe index for which the repeated transmission is to be terminated is M, the controller controls the transmitter 1120 such that the downlink subframe index at which the PDSCH repeated transmission starts is M + k. The controller 1110 may control the transmitter 1120 such that the value of k is an integer greater than or equal to zero. The controller 1110 controls the transmission unit 1120 to transmit the PDSCH / EPDCCH repeatedly. In an embodiment, the controller 1110 may control the transmitter 1120 such that the value of k is equal to one. Also, the terminal may be a terminal supporting MTC. The controller 1110 may control the transmitter 1120 such that the value of P, which is the number of times the PDSCH is repeatedly transmitted, has an integer value of 1 or more. The controller 1110 can determine the P by using one of the format of the PDCCH or the EPDCCH and the N in the same manner as the method of functionizing the information on the PDSCH repetitive transmission in the method 2.

12 is a diagram illustrating a configuration of a user terminal according to another embodiment of the present invention.

12, the user terminal 1200 according to another embodiment includes a receiving unit 1230, a control unit 1210, and a transmitting unit 1220.

The receiving unit 1230 receives downlink control information, data, and messages from the base station through the corresponding channel.

Also, the controller 1210 is a PDCCH / EPDCCH transmission method for DL allocation DCI transmission including PDSCH scheduling information for a MTC terminal for performing the above-described present invention, and includes a PDCCH / EPDCCH transmission downlink The overall operation of the UE is controlled by performing the downlink data channel transmission / reception method for the MTC terminal in which the relationship between the link sub-frame and the PDSCH transmission downlink sub-frame is specified.

The transmitter 1220 transmits uplink control information, data, and a message to the base station through the corresponding channel.

In more detail, the UE of FIG. 12 receives a PDCCH or an EPDCCH including PDSCH scheduling information from the BS and the PDSCH accordingly, and repeatedly receives the PDCCH or EPDCCH.

The receiver 1230 repeatedly receives the PDCCH or the EPDCCH through N downlink subframes, and repeatedly receives the PDSCH through P downlink subframes. If the downlink subframe index for which the repeated reception of the PDCCH or the EPDCCH is M is performed, the control unit 1210 controls the reception unit 1230 such that the downlink subframe index at which the PDSCH repeated reception starts is M + k. . That is, the receiving unit 1230 repeatedly receives the PDCCH or the EPDCCH through N downlink subframes and repeatedly receives the PDSCH through P downlink subframes, and the controller 1210 receives the PDCCH or the EPDCCH If the downlink subframe index for which the repeated reception is terminated is M, the downlink subframe index at which the PDSCH repeated reception starts is controlled by the reception unit 1230 to be M + k. The controller 1210 may control the receiver 1230 such that the value of k is an integer greater than or equal to zero. The controller 1210 controls the reception unit 1230 to transmit the PDSCH / EPDCCH repeatedly. In one embodiment, the controller 1210 may control the receiver 1230 such that the value of k is 1. Also, the terminal 1200 may be a terminal supporting MTC. The controller 1210 may control the receiver 1230 such that the value of P, which is the number of times the PDSCH is repeatedly transmitted, has an integer value of 1 or more. The controller 1210 can determine the P by using one of the format of the PDCCH or the EPDCCH and the N in the same manner as the method of functionizing the information on the PDSCH repetition transmission in the method 2.

A PDCCH / EPDCCH transmission method for DL allocation DCI transmission including PDSCH scheduling information in a base station for a MTC terminal has been described in which a PDCCH / EPDCCH transmission downlink subframe including DL allocation and a PDSCH transmission downlink subframe And a method and an apparatus for transmitting and receiving a downlink data channel for a MTC terminal having a specified relationship have been described.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (24)

A method for transmitting a Physical Downlink Control Channel (PDCCH) or an Enhanced Physical Downlink Control Channel (EPDCCH) including PDSCH (Physical Downlink Shared CHannel) scheduling information for a UE and the PDSCH according to the Node B,
Repeatedly transmitting the PDCCH or the EPDCCH through N downlink subframes; And
Repeatedly transmitting the PDSCH through P downlink subframes,
And the downlink subframe index at which the repeated transmission of the PDCCH or the EPDCCH ends is M, the downlink subframe index at which the PDSCH repeated transmission starts is M + k. The method according to claim 1,
Wherein the value of k has an integer value of zero or more. The method according to claim 1,
Wherein the value of k is one. The method according to claim 1,
Wherein the terminal is a terminal supporting MTC (Machine Type Communications). The method according to claim 1,
Wherein the value of P has an integer value of 1 or more. The method according to claim 1,
Wherein the P is determined using at least one of the format of the PDCCH or the EPDCCH and the N. [ A method for receiving a Physical Downlink Control Channel (PDCCH) or an Enhanced Physical Downlink Control Channel (EPDCCH) including PDSCH (Physical Downlink Shared CHannel) scheduling information from a Node B and a corresponding PDSCH,
Repeatedly receiving the PDCCH or the EPDCCH through N downlink subframes; And
Repeatedly receiving the PDSCH through P downlink subframes,
Wherein the downlink subframe index in which the repeated reception of the PDCCH or the EPDCCH is ended is M, the downlink subframe index at which the PDSCH repeated reception starts is M + k. 8. The method of claim 7,
Wherein the value of k has an integer value of zero or more. 8. The method of claim 7,
Wherein the value of k is one. 8. The method of claim 7,
Wherein the terminal is a terminal supporting MTC (Machine Type Communications). 8. The method of claim 7,
Wherein the value of P has an integer value of 1 or more. 8. The method of claim 7,
Wherein the P is determined using at least one of the format of the PDCCH or the EPDCCH and the N. [ A base station for transmitting a Physical Downlink Control Channel (PDCCH) or an Enhanced Physical Downlink Control Channel (EPDCCH) including PDSCH (Physical Downlink Shared CHannel) scheduling information for a UE and the PDSCH,
A transmitter for repeatedly transmitting the PDCCH or the EPDCCH through N downlink subframes and repeatedly transmitting the PDSCH through P downlink subframes; And
And a controller for controlling the transmitter so that the downlink subframe index at which the repeated transmission of the PDCCH or the EPDCCH ends is M, when the downlink subframe index at which the repeated transmission of the PDCCH or the EPDCCH ends is M, the downlink subframe index at which the PDSCH repeated transmission starts is M + k. 14. The method of claim 13,
Wherein the controller controls the transmitter to have the value of k equal to or greater than zero. 14. The method of claim 13,
Wherein the control unit controls the transmitter so that the value of k is 1. 14. The method of claim 13,
Wherein the terminal is a terminal supporting MTC (Machine Type Communications). 14. The method of claim 13,
Wherein the control unit controls the transmission unit such that the value of P has an integer value of 1 or more. 14. The method of claim 13,
Wherein the controller determines the P by using the format of the PDCCH or the EPDCCH and the N or more. A terminal for receiving a Physical Downlink Control Channel (PDCCH) or an Enhanced Physical Downlink Control Channel (EPDCCH) including PDSCH (Physical Downlink Shared CHannel) scheduling information from a base station and the PDSCH corresponding thereto,
A receiver repeatedly receiving the PDCCH or the EPDCCH through N downlink subframes and repeatedly receiving the PDSCH through P downlink subframes; And
And a controller for controlling the receiver such that the downlink subframe index at which the PDCCH repetition reception starts is M + k when the downlink subframe index at which the repeated reception of the PDCCH or the EPDCCH is terminated is M. 20. The method of claim 19,
Wherein the control unit controls the always-reception unit so that the value of k has an integer value of 0 or more. 20. The method of claim 19,
Wherein the control unit controls the receiving unit such that the value of k is equal to one. 20. The method of claim 19,
Wherein the terminal is a terminal supporting MTC (Machine Type Communications). 20. The method of claim 19,
Wherein the control unit controls the receiver so that the value of P has an integer value of 1 or more. 20. The method of claim 19,
Wherein the controller determines the P by using the format of the PDCCH or the EPDCCH and the N or more.

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