KR101574713B1 - Method for transmitting control information, transmission/reception point thereof, method for receiving control information and terminal thereof - Google Patents

Abstract

The present invention relates to a control information transmission method for a transmission / reception point for a UE receiving downlink control information through a downlink control channel introduced in a data area, a control information reception method and apparatus for the UE, and an ECCE an enhanced Control Channel Element).

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control information transmission method of a transmission / reception point, a transmission / reception point of the transmission / reception point, a control information reception method of a terminal, and a terminal thereof,

The present invention relates to a control information transmission method of a transmission / reception point for a terminal that receives downlink control information through a downlink control channel introduced in a data area, and a control information reception method and apparatus thereof.

In a wireless communication system capable of transmitting data to a larger number of users, the system capacity increase is limited due to the resources of the conventional limited control region. Therefore, it is necessary to transmit downlink control information through the downlink control channel located in the data region.

Meanwhile, a new control channel element for assigning a downlink control channel located in a data area corresponding to a control channel element for assigning a downlink control channel in an existing control domain A resource allocation method is required.

The present invention provides an Enhanced Control Channel Element (ECCE) / Enhanced Resource Element Group (EREG) mapping method for downlink control channel transmission in a data area. Also provided is a method and apparatus for indexing ECCEs in any centralized Enhanced Physical Downlink Control Channel (EPDCCH) set.

A control information transmission method of a transmission / reception point for transmitting control information to a terminal through a data area of a physical resource block pair of a subframe, the method comprising the steps of: The remainder divided by 4 of the resource elements constituted by the resource elements having the same index with respect to the indexed resource elements is divided into resource element groups corresponding to the same index or remainder divided by 2 Assigning control channel elements to resource element groups corresponding to the same index, and transmitting control information to a terminal via at least one control channel element of the control channel elements. ≪ / RTI >

A control information receiving method of a terminal for receiving control information from a transmitting / receiving point through a data area of a physical resource block pair of a subframe, the method comprising the steps of: The remainder divided into four of the resource elements constituted by the resource elements having the same index with respect to the indexed resource elements is allocated to the resource element groups corresponding to the same index, Receiving a radio signal through at least one control channel element among control channel elements assigned to resource element groups corresponding to the same index, and obtaining the control information from the radio signal, The method comprising:

A transmission / reception point for transmitting control information to a terminal through a data area of a physical resource block pair of a subframe. The resource element is a resource element for assigning an index by repeating 16 numbers in a frequency- The resource element groups corresponding to the same index or the remainder divided by 2 in the remainder divided by 4 out of the enhanced resource groups composed of the resource elements having the same index with respect to the Resource Elements correspond to the same index And a transmitter for transmitting control information to at least one of the control channel elements through at least one of the control channel elements.

The present invention relates to a method and apparatus for receiving control information from a transmission / reception point through a data area of a physical resource block pair of a subframe, The remainder divided by 4 of the resource element groups composed of the resource elements having the same index with respect to the Resource Elements is allocated to resource element groups corresponding to the same index, And a control unit for acquiring the control information from the radio signal. The present invention also relates to a control method for a mobile communication system.

1 shows an example of a wireless communication system to which embodiments are applied.
FIG. 2 shows one resource block pair in the case of a normal cyclic prefix (CP) as an example of the structure of downlink resources in a LTE (Long Term Evolution) or LTE-Advanced (LTE-Advanced) system.
3 illustrates an example of RE (Resource Element) mapping of an EREG-indexed PRB (physical resource block) pair with symbol-based cyclic shift to one transmit antenna port (cell-specific reference signal port (CRS) .
Figure 4 is an example of an RE mapping of an EREG indexed PRB pair with symbol-based cyclic shifts for two transmit antenna ports (CRS ports 0, 1).
Figure 5 is an illustration of an RE mapping of an EREG indexed PRB pair with symbol-based cyclic shifts for four transmit antenna ports (CRS ports 0, 1, 2, 3).
6 is an exemplary RE mapping of an EREG indexed PRB pair with no cyclic shift for one transmit antenna port (CRS port 0).
FIG. 7 is an illustration of an RE mapping of an EREG indexed PRB pair with no cyclic shift for two transmit antenna ports (CRS ports 0, 1).
FIG. 8 is an illustration of an RE mapping of an EREG indexed PRB pair with no cyclic shift for four transmit antenna ports (CRS ports 0, 1, 2, 3).
9 is an exemplary EREG mapping of a centralized EPDCCH set according to the first and second embodiments.
10 is a flowchart illustrating a method of transmitting control information of a transmission / reception point according to an embodiment of the present invention.
11 is a flowchart illustrating a method of receiving control information of a UE according to another embodiment of the present invention.
12 is a diagram illustrating a configuration of a transmission / reception point according to another embodiment of the present invention.
13 is a diagram illustrating a configuration of a UE 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.

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 transmission / reception point. 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 (BS) or a cell, a Node-B, an evolved Node-B (eNB), a sector (Sector) ), A site, a base transceiver system (BTS), an access point, a relay node, a remote radio head (RRH), and a radio unit (RU).

That is, the base station or the cell in this specification is interpreted as a comprehensive meaning indicating a partial region or function covered by BSC (Base Station Controller) in CDMA, NodeB in WCDMA, eNB in LTE or sector (site) And covers various coverage areas such as a megacell, a macro cell, a microcell, a picocell, a femtocell and a relay node, a remote radio head (RRH), and a communication range of an RU (radio unit).

In this specification, a user terminal and a transmission / reception point are used in a generic sense as two transmitting and receiving subjects used to implement the technical or technical idea described in the present specification, and are not limited by a specific term or word. The user terminal and the transmission / reception point are used in a broad sense as two (uplink or downlink) transmission / reception subjects used to implement the technical 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, 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-A, the uplink and downlink are configured on the basis of one carrier or carrier pair to form a standard. The uplink and downlink transmit control information through a control channel such as a Physical Downlink Control Channel (PDCCH), a Physical Control Format Indicator CHannel (PCFICH), a Physical Hybrid ARQ Indicator CHannel (PHICH), a Physical Uplink Control CHannel And a data channel such as a Physical Downlink Shared CHannel (PDSCH), a Physical Uplink Shared CHannel (PUSCH), and the like.

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 . Herein, the transmission / reception point means a transmission point for transmitting / transmitting a signal or a reception point for receiving a signal or a transmission / reception point thereof.

1 shows an example of a wireless communication system to which embodiments are applied.

Referring to FIG. 1, a wireless communication system 100 to which embodiments are applied includes a coordinated multi-point transmission / reception system (CoMP system) in which two or more transmission / reception points cooperatively transmit signals, A coordinated multi-antenna transmission system, and a cooperative multi-cell communication system. CoMP system 100 may include at least two transmit and receive points 110 and 112 and terminals 120 and 122.

The transmission / reception point has a high transmission power, which is connected to a base station or a macro cell (hereinafter referred to as 'eNB') 110 and an eNB 110 through an optical cable or an optical fiber, Or at least one RRH 112 with the same number of RRs. The eNB 110 and the RRH 112 may have the same cell ID or different cell IDs.

Hereinafter, a downlink refers to a communication or communication path from the transmission / reception point 110 or 112 to the terminal 120, and an uplink refers to communication from the terminal 120 to the transmission / reception point 110 or 112 Or a communication path. In the downlink, the transmitter may be part of the transmission / reception point 110, 112, and the receiver may be part of the terminal 120, 122. In the uplink, the transmitter may be part of the terminal 120, and the receiver may be part of the transmission / reception point 110, 112.

Hereinafter, a situation in which a signal is transmitted and received through a channel such as a Physical Uplink Control Channel (PUCCH), a Physical Uplink Shared Channel (PUSCH), a Physical Downlink Control Channel (PDCCH), and a Physical Downlink Shared Channel (PDSCH) is referred to as a PUCCH, PDSCH is transmitted and received.

The eNB performs downlink transmission to the UEs. 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.

In wireless communication, one radio frame (radio frame) is composed of 10 subframes, and one subframe is composed of two slots. The radio frame has a length of 10 ms and the subframe has a length of 1.0 ms. In general, a basic unit of data transmission is a subframe unit, and downlink or uplink scheduling is performed in units of subframes. One slot includes Orthogonal Frequency Division Modulation (OFDM) symbols of seven (in case of normal cyclic prefix) or six (in case of extended cyclic prefix) in the time domain.

In the radio communication, the frequency domain may be composed of, for example, subcarrier units of 15 kHz intervals.

In the downlink, time-frequency resources can be set in units of resource blocks (RBs). The resource block may consist of one slot on the time axis and 180 kHz (12 subcarriers) on the frequency axis. A resource consisting of 12 subcarriers in one subcarrier (two slots) frequency axis on the time axis can be referred to as a resource block pair (RBP). The number of total resource blocks varies depending on the system bandwidth.

A Resource Element (RE) can be composed of one OFDM symbol on the time axis and one subcarrier on the frequency axis. One resource block pair may contain resource elements of 14X12 (for normal CP) or 12X12 (for extended CP).

FIG. 2 shows one resource block pair in the case of a normal cyclic prefix (CP) as an example of the structure of downlink resources in a LTE (Long Term Evolution) or LTE-Advanced (LTE-Advanced) system.

Referring to FIG. 2, one resource block pair in the case of a normal CP is composed of 14 OFDM symbols (l = 0 to 13) and 12 subcarriers (k = 0 to 11). In the example of FIG. 2, an area (l = 0 to 2) consisting of three OFDM symbols in front of the 14 OFDM symbols belonging to one resource block pair is composed of a Physical Control Format Information CHannel (PCFICH), a Physical Hybrid ARQ Indicator 3 to 13 are allocated for a data channel such as a PDSCH (Physical Downlink Shared CHannel), and the remaining regions (l = 3 to 13) are allocated for a data channel such as a Physical Downlink Shared CHannel (PDSCH) Data area 220, as shown in FIG. Although it is shown that three OFDM symbols are allocated for the control domain 210 in FIG. 2, it is possible for one to four OFDM symbols to be allocated for the control domain 210. The size information of the OFDM symbol in the control area 210 may be transmitted via the PCFICH.

The PDCCH can be transmitted over the entire system band, and the PDSCH can be transmitted on a resource block basis. The user terminal may first determine the PDCCH set for itself and then reduce the power consumption of the user terminal in the data area 120 by taking a micro sleep mode when there is no corresponding data.

Referring to FIG. 2, a reference signal may be mapped to a specific resource element of the downlink. In the downlink, a common reference signal, a common reference signal or a cell-specific reference signal (CRS) 230, a demodulation reference signal, or a UE-specific reference signal (DM-RS) 232 and 234, a channel status information reference signal (CSI-RS), and the like. In FIG. 2, only the CRS 230 and the DM-RSs 232 and 234 are shown for convenience of explanation.

The CRS 230 in the control region 210 may be used for channel estimation for decoding the PDCCH and the CRS 230 in the data region 220 may be used for downlink channel measurements. Channel estimation for data decoding of the data area 220 may be performed using DM-RSs 232 and 234. The DM-RSs 232 and 234 are multiplexed with a reference signal for a plurality of layers using an orthogonal code. For example, in the case of four-layer transmission, two orthogonal codes of length 2 can be applied to two consecutive reference signal resource elements on a time axis to multiplex two different reference signals for each reference signal group, and eight In the case of layer transmission, orthogonal signals of length 4 can be applied to four reference signal resource elements dispersed on the time axis, thereby multiplexing four different reference signals for each reference signal group.

In the case of one or two layer transmission, since the reference signals of the respective layers can be transmitted using only one DM-RS group 1 232, another DM-RS group 2 234 can be used for data transmission have. The DM-RS corresponding to each layer is transmitted by applying the same precoding applied to the corresponding layer. This makes it possible to decode data at the receiving end (terminal) without the precoding information applied at the transmitting end (base station).

A control channel is needed to efficiently utilize limited resources in a wireless communication system. However, the resources of the control area 210 reduce the resources of the data area 220 used for data transmission as an overhead of the system. In the OFDM-based LTE system, one resource block pair is composed of 14 or 12 OFDM symbols. Of the OFDM symbols, a maximum of 3 OFDM symbols are used for the control domain 210, and the remaining OFDM symbols are used for the data domain 220 . On the other hand, in the LTE-A system capable of transmitting data to a larger number of users, system capacity increase can be restricted due to the resources of the conventional limited control region 210. Therefore, an increase in control channel resources is inevitable, so that a control channel transmission / reception method of multiple users using the spatial division multiplexing technique in the data area 220 can be considered. This method is to send and receive a control channel in the data area 220. For example, the control channel transmitted in the data area 220 may be called EPDCCH (Extended PDCCH or Enhanced PDCCH), but is not limited thereto.

In the conventional 3GPP LTE / LTE-A rel-8/9/10 system, all UEs receive 1 ~ 3 OFDM symbols (system band> 10 PRBs) Lt; / RTI > OFDM symbols (system band < RTI ID = 0.0 ># 10 PRBs). ≪ / RTI > A basic unit of the PDCCH transmission for an arbitrary terminal is a control channel element (CCE), and one CCE is composed of nine resource element groups (REG). One REG includes REs excluding REs (Resource Elements) to which PCFICH and PHICH, which are other physical channels existing in the PDCCH region of the DL subframe, and a cell-specific reference signal (CRS) For example, by grouping four consecutive REs on the frequency axis.

Unlike the legacy PDCCH, the EPDCCH newly introduced in 3GPP LTE / LTE-A release 11 and subsequent systems is transmitted through the PDSCH region of the downlink pilot time slot (DwPTS) of the downlink subframe or the special subframe , And M groups of M PRBs (M is a natural number equal to or smaller than the number of PRBs in all the bands) of M or more for each UE set to receive DCI (Downlink Control Information) through the corresponding EPDCCH It is defined to allocate the set EPDCCH set in the corresponding cell up to K (maximum value of K can be one of 2, 3, 4 & 6). Also, each EPDCCH set set for an arbitrary terminal may have a different K value.

Depending on the EPDCCH transmission type, the EPDCCH set may be a localized type or a distributed type, where X is 1 or 2 ⁿ (n = 1, 2, 3, 4 , 5). While X may be 2, 4, 8, 16 in the decentralized form, but is not limited thereto.

(K = 1) ePDCCH set can be allocated for one UE. Since each ePDCCH set is a distributed type or a centralized type, the number of KL distributed type ePDCCH and KD distributed Type ePDCCH may be assigned. That is, KL + KD = K can be obtained.

An EREG (Enhanced REG) / ECCE (Enhanced CCE) may be introduced into the EPDCCH corresponding to the concept of REG and CCE of the conventional PDCCH for EPDCCH transmission resource mapping for an arbitrary terminal.

According to the newly introduced EREG / ECCE, not only a frame structure type, a subframe configuration, a CP (Cyclic Prefix) length but also a legacy PDCCH control are set for one PRB pair constituting each EPDCCH set A total of 16 EREGs from EREG # 0 to EREG # 15 are configured in the corresponding PRB pair irrespective of whether or not the reference signal (for example, CRS, CSI-RS, PRS, etc.) can do.

Specifically, for a normal CP for one PRB pair constituting an arbitrary EPDCCH set, 16 numbers are allocated to 144 REs excluding 24 REs for a DM-RS among a total of 12 x 14 = 168 REs EREG indexing can be done from 0 to 15 in frequency first and then time manner. Likewise, in the case of the extended CP, for the 128 REs except for the 16 REs for the DM-RS out of the 12 x 12 = 144 REs constituting one PRB pair, 16 numbers are allocated in the frequency first and then time manner, the EREG can be indexed from 0 to 15.

An example of EREG indexing in one PRB pair constituting an arbitrary EPDCCH set in a DL subframe corresponding to a normal CP is shown in FIGS. 3 to 8 below. 3 to 8 below, RE indicates the RE used for the DM-RS, and the part denoted by the lattice or shaded area is the RE to which the CRS is transmitted .

3 is an illustration of an RE mapping of an EREG indexed PRB pair with a symbol-based cyclic shift for one transmit antenna port (CRS port 0).

Referring to FIG. 3, EREGs are indexed in a frequency-preferential manner from 0 to 15, indexes are indexed by a symbol-based cyclic shift, and indices 12 of the second symbol are indexed adjacent to the index 11 of the first symbol . In the same manner, index 8 of the third symbol is indexed adjacent to index 7 of the second symbol.

The PRB pair shown in FIG. 3 is for CRS port 0, and CRS is mapped to 8 REs as shown in FIG. The CRS may be mapped to another location by frequency shifts.

Figure 4 is an exemplary RE mapping of an EREG indexed PRB pair with symbol-based cyclic shifts for two transmit antenna ports (CRS ports 0, 1) 2, 3) of an EREG-indexed PRB pair with a symbol-based cyclic shift.

4 and 5 are indexed with a symbol-based cyclic shift in the same manner as shown in FIG. 3, and FIG. 4 shows an example in which, in addition to the CRS shown in FIG. 3 for CRS port 0, RE is mapped to CRS, and FIG. 5 maps CRS to eight additional REs in addition to the CRS shown in FIG. 4 for CRS ports 0, 1, 2, and 3.

The example of FIGS. 3 to 5 described above is an example in which a cyclic shift is applied when EREG indexing is performed for each OFDM symbol, and FIGS. 6 to 8 to be described later are examples in which a cyclic shift is not applied .

6 is an exemplary RE mapping of an EREG indexed PRB pair with no cyclic shift for one transmit antenna port (CRS port 0), and FIG. 8 is an exemplary RE mapping of an EREG-indexed PRB pair with no cyclic shift for four transmit antenna ports (CRS ports 0, 1, 2, 3) .

6 to 8 are mapped CRSs in the same manner as the CRS mapping of Figs. 3 to 5, respectively. However, there is a difference in the way of indexing.

6, the EREG is indexed in a frequency-preferential manner with numbers from 0 to 15, indexed without symbol-based cyclic shift, index 12 of the second symbol is indexed adjacent to index 11 of the first symbol, And is indexed away. In the same way, index 8 of the third symbol, the next sequential of index 7 of the second symbol, is indexed without being adjacent.

In FIGS. 3 to 8, REs having the same index are grouped into one EREG. Therefore, a total of 16 EREGs are allocated from EREG # 0 to EREG # 15 for one PRB pair. FIGS. 3 to 8 show an example of the PRB pair of the normal CP, but a total of 16 EREGs are allocated to the PRB pair of the extended CP from EREG # 0 to EREG # 15 in the same manner.

Referring to FIG. 3 to FIG. 8, each EREG # 0, EREG # 1, ..., EREG # , And EREG # 15 may each be composed of nine REs. However, the number of REs that can be actually used for EPDCCH transmission for each EREG can be changed by the number of transmission antenna ports (CRS port number) and the size of the legacy PDCCH, as shown in the above figure.

Referring again to FIG. 3, if there are nine REs corresponding to the index # 0, and if the third up to the third RE is set as a control region, the REs corresponding to the RE # And EREG # 0 are all composed of 6 available REs. In the case of the EREG corresponding to the index # 1, 9 REs indexed to # 1 are available. EREG # 1 can be used for 5 except for the control region up to the third control region and the RE region to which the CRS is mapped RE.

The ECCE, which is the basic unit of the EPDCCH transmission, can be composed of N EREGs, respectively, according to the subframe type and the CP length. Specifically, the above-mentioned N value can be determined as follows.

First, N = 4 may be set for 3, 4 and 8 of the special subframes corresponding to the normal subframe and the normal CP corresponding to the normal CP. That is, in this case, a total of 4 ECCEs can be constituted by four EREGs for 16 EREGs constituting one PRB pair.

In other cases, the normal subframe corresponding to the extended CP, the special subframes 1, 2, 6, 7 and 9 corresponding to the normal CP, and the special subframes 1, 2, 3, 5 and 6, N = 8. In this case, a total of 2 ECCEs can be constituted by eight EREGs for 16 EREGs constituting one PRB pair.

In the case of the conventional PDCCH, in the case of a normal DL subframe, transmission is performed through the first to third OFDM symbols or 2 to 4 OFDM symbols, and nine REGs constitute one CCE . Therefore, PDCCH CCEs can be composed of 9X4 = 36 REs.

However, in the case of the EPDCCH, as described with reference to FIG. 3 to FIG. 8, it is possible to use the legacy control region size (i.e., the legacy PDCCH size) and REs used as other reference signals such as CRS and CSI- Since indexing has been performed, the number of REs that can be actually used for EPDCCH transmission varies depending on the size of the legacy control region in any downlink subframe and the presence of other reference signals.

That is, the number of REs available for EPDCCH transmission may be different for each EREG. Therefore, in the case of an ECCE serving as a basic unit of an actual EPDCCH transmission, there is a possibility that an imbalance occurs in the number of REs actually available for each ECCE.

The present invention provides a method of mapping an EREG constituting each ECCE in consideration of such a problem. In particular, the present invention provides an ECCE / EREG mapping method in a localized type EPDCCH set.

Specifically, the present invention provides a method of constructing each ECCE in a pair of PRBs constituting a localized type EPDCCH set as described above. In particular, in consideration of the legacy PDCCH and the CRS transmitted through the DwPTS region of all downlink subframes and special subframes, an optimal ECCE / EREG mapping considering the number of REs that can be used for EPDCCH transmission in a corresponding PRB pair ≪ / RTI >

[Embodiment 1] ECCE configuration with N consecutive EREGs

Embodiment 1 provides a method of configuring N consecutive EREGs in one PRB pair constituting an EPDCCH set into one ECCE and thus a method of indexing an ECCE.

Table 1 is a table summarizing the number of REs available for each EREG according to each CRS port setting when the legacy PDCCH size is 1.

 Table 1 summarizes EREG indexing based on no cyclic shift. Since one ECCE is composed of four EREGs (N = 4) in the corresponding subframe, when one ECRE is formed by grouping four consecutive ECREs according to the first embodiment, EREGs constituting each ECCE and The number of REs available for each ECCE is shown in Table 2.

For four transmit antenna ports (4 Tx CRS), there are 26 available REs for 1 ^st ECCEs and 33 available REs for 4 ^th ECCEs, differing by 7 REs from each other. As a result, the imbalance between the available REs constituting each ECCE becomes large.

This has similar characteristics when the legacy PDCCH size is 2 (Table 3) and 3 (Table 5).

Table 3 is a table summarizing the number of REs available for each EREG according to each CRS port setting when the legacy PDCCH size is 2. Table 4 shows the number of REs that can be used by each ECCE and the number of REs that can be used by each ECCE when constructing one ECCE by grouping four consecutive EREGs in the same situation as in Table 3. Table 4:

For four transmit antenna ports (4 Tx CRS), there are 22 available REs for 1 ^st ECCEs and 29 available REs for 4 ^th ECCEs with a difference of 7 REs from each other.

Table 5 is a table summarizing the number of REs available for each EREG according to each CRS port setting when the legacy PDCCH size is 3. Table 5 shows the number of REs that can be used by each ECCE and the number of REs that can be used by each ECCE when each ECCE is composed by grouping four consecutive EREGs in the same situation as shown in Table 5. [

For four transmit antenna ports (4 Tx CRS), there are 18 available REs for 1 ^st ECCE and 25 available REs for 4 ^th ECCE, with a difference of 7 REs from each other.

Accordingly, when a set of EPDCCHs in a given EPDCCH set composed of M PRBs (a group of X PRBs) (X is 2, 4, 8, 16) is a localized type, The ECCEs constituting the corresponding EPDCCH set may be configured as follows according to the first embodiment.

Specifically, ECCEs constructed according to the first embodiment can be indexed in ascending order from the lowest PRB pair (the PRB pair having the smallest PRB index) for M PRBs constituting any concentrated type EPDCCH set.

Referring to (a) of Figure 9, lowest PRB pair in EREG # 0 ~ EREG # 3 as consisting of 1 ^st ECCE the ECCE # and 0, respectively EREG # 4 ~ EREG # 7 2 nd ECCE the ECCE # 1 consisting of , EREG # 8 ~ is the 3 ^rd ECCE consisting EREG # 11 ECCE # 2, EREG # 12 ~ EREG # 15 4 th ECCE consisting are each indexed by the ECCE # 3. Then each Similarly, in PRB pair having a second lowest PRB index EREG # 0 ~ 3, EREG # 4 ~ 7, EREG # 8 ~ 11, EREG # 12 ~ 15 , each of the 1 ^st, 2 ^nd consisting of, 3 ^rd, 4 ^th ECCEs are indexed with ECCE # 4, ECCE # 5, ECCE # 6, and ECCE # 7, respectively. In this way, ECCE # (4M-4), ECCE # (4M-3), ECCE # 4M-2 and ECCE # 4M- 4 up to the four ECCEs constituted in the PRB pair having the last M- 1), ECCE indexing of the corresponding centralized EPDCCH set and EREG mapping constituting each ECCE can be performed.

Alternatively, 1 ^st ECCEs consisting of EREG # 0, # 1, # 2, and # 3 can be indexed in order from the PRB pair for M PRBs constituting an arbitrary concentrated EPDCCH set.

Referring to FIG. 9B, M ECCEs from 1 ^st ECCE composed of EREG # 0 to EREG # 3 of lowest PRB to ECCEs composed of EREG # 0 to EREG # 3 of Mth lowest PRB (largest PRB index) To ECCE # 0 to ECCE # (M-1) in order of the indexes of the PRBs containing the corresponding ECCEs. Then, for M 2 ^nd ECCEs consisting of EREG # 4, # 5, # 6, and # 7 in each PRB pair, ECCE #M to ECCE # (2M-1 ), Indexes ECCE # 2M to ECCE # (3M-1) in ascending order of the PRB index for 3 ^rd ECCEs composed of EREG # 8 to EREG # 11 of each PRB pair, Similarly, also for the 4 ^th ECCE consisting EREG # 12 ~ # 15 EREG of each PRB pair can be indexed to the ECCE # 3M ~ ECCE # (4M -1).

[Example 2] Construction of ECCE with EREG having the same remainder divided by 4 (or 2)

As can be seen from the above, simply constructing a single ECCE by grouping four successive EREGs increases the real number of REs that can be used for each ECCE. In fact, the main reason for causing the imbalance is that the use of 12 consecutive REs corresponding to one OFDM symbol is determined according to the size of the legacy PDCCH. That is, the gap between the EREGs corresponding to 12 consecutive REs among the 16 EREGs and the 4 consecutive EREGs not corresponding thereto will be generated.

In order to solve this problem, the second embodiment provides a method of constructing one ECCE by grouping EREG indexes having the same remainder by dividing the EREG index value into four by taking modulo 4 in one PRB pair constituting the EPDCCH set.

Accordingly, each ECCE can be configured as follows.

1 ^st ECCE: EREG #n (n mod 4) = 0

2 ^nd ECCE: EREG #n with (n mod 4) = 1

3 ^rd ECCE: EREG #n (n mod 4) = 2

4 ^th ECCE: EREG #n with (n mod 4) = 3

At this time, n = 0, 1, 2, ..., 15 and n is the EREG index shown in Figs.

I.e., 1 ^st ECCE in the PRB pair in any EPDCCH set is EREG # 0, EREG # 4, EREG # 8, is composed of EREG # 12, 2 ^nd ECCE is EREG # 1, EREG # 5, EREG # 9, EREG # 13. The 3 ^rd ECCE consists of EREG # 2, EREG # 6, EREG # 10 and EREG # 14. The 4 ^th ECCE consists of EREG # 3, EREG # 7, EREG # 11 and EREG # do. When constructing the ECCE in this way, the available RE according to the size of the legacy PDCCH for each ECCE can be calculated as follows.

When the size of the legacy PDCCH is 1, the number of REs constituting each ECCE and the number of REs available for each ECCE are configured as shown in Table 7. [

When the size of the legacy PDCCH is 2, the number of REs constituting each ECCE and the number of REs available for each ECCE are configured as shown in Table 8.

When the size of the legacy PDCCH is 3, the number of REs constituting each ECCE and the number of REs available for each ECCE are configured as shown in Table 9. [

When the EREG index value is modulo 4 in one PRB pair constituting the EPDCCH set, four EREGs having the same EREG index value are grouped together to form one ECCE, thereby eliminating the imbalance in the number of available REs between ECCEs .

This can be applied equally to cyclic shifts when indexing EREGs for each OFDM symbol.

Accordingly, when the set of EPDCCHs in an arbitrary EPDCCH set composed of M PRB (Physical Resource Block) groups is a localized type, the ECCEs constituting the corresponding EPDCCH set can be configured as follows according to Embodiment 2 have.

Even if it is based on the second embodiment, according to the two methods based on the embodiment 1, the 1 ^st ECCE of the lowest PRB pair (the PRB pair having the smallest PRB index) for the M PRBs constituting the centralized EPDCCH set in the embodiment the PRB pairs according to example 2 EREG # 0, # 4, # 8, # 12 as configured ECCE) from the M-th lowest PRB index (that is, largest PRB index) for having PRB pair of the 4 ^th ECCE (the PRB ECCE # 0, ECCE # 1, ..., and ECCE # (4M-1) up to the ECCEs of the pairs EREG # 3, 7, 11,

Referring again to FIG. 9 (a), a 1 ^st ECCE composed of EREG # 0, # 4, # 8, and # 12 of the lowest PRB pair for M PRBs constituting each arbitrary concentrated type EPDCCH set 2 ^nd ECCEs composed of EREGs # 1, # 5, # 9 and # 13 are indexed into ECCE # 1 and indexed with ECCE # 0 and 3 ^rd ECCEs composed of EREG # 2, # 6, # 10 and # EREG # 3, # 7, # 11, # 15 4 th may ECCE can each be indexed to the ECCE # 2, # 3 consisting of ECCE. Then, it is indexed to the respective ECCE # 4 ~ # 7 ECCE in the same sequence in the 2 ^nd lowest PRB pair. In this manner, the 4 ^th ECCE of the PRB pair having the last Mth lowest PRB index (the ECCE consisting of EREG # 3, 7, 11, 15 of the corresponding PRB pair) is set to ECCE # 4M-1 Indexed < / RTI >

Referring again to FIG. 9A, the 1 ^st ECCE of each PRB pair (ECCEs consisting of EREG # 0, # 4, # 8, and # 12 in each PRB pair) Indexed up to ECCE # M to ECCE # (M-1), then indexed to ECCE # M to ECCE # (2M-1) in the same order for 2 ^nd ECCEs of each PRB pair, 3 ECCE # 3M to ECCE # (3M-1) for the 3 ^rd ECCEs and ECCE # 3M to ECCE # (4M-1) for the last 4 ^th ECCEs of each PRB pair.

Until now, the normal subframe of the normal CP and the special subframes 3, 4, 8 (normal subframe) corresponding to the number of EREGs constituting the one ECCE (i.e., when N = 4) an ECCE / EREG mapping method and an ECCE indexing method in any concentrated type EPDCCH set applicable in a normal CP are described.

Similarly, if the number of EREGs constituting one ECCE is eight (that is, the case of N = 8), a downlink subframe of the extended CP, a special subframe 1, The ECCE / EREG mapping method and the ECCE indexing method according to the same method can also be applied to the concentrated type EPDCCH set set in 7,9 (normal CP) and special subframes 1,2,3,5,6 (extended CP) .

That is, in the first embodiment, instead of configuring four ECCEs by grouping four consecutive EREGs out of the 16 EREGs constituting the corresponding PRB pair for an arbitrary PRB pair constituting an arbitrary concentrated EPDCCH set, 8 1 ^st ECCEs (EREG # 0 to EREG # 7) and 2 ^nd ECCEs (EREG # 8 to EREG # 15) can be configured by grouping the EREGs. Likewise, in the second embodiment, when modulo 4 is taken for 16 EREGs constituting a PRB pair for an arbitrary PRB pair constituting an arbitrary concentrated EPDCCH set, four EREGs having the same EREG index value It is possible to construct each ECCE with eight EREGs having the same EREG index value when modulo 2 is taken, instead of forming one ECCE each. That is, a 1 ^st ECCE is configured in each pair of PRBs (EREG # 0, # 2, # 4, # 6, # 8, # 10, # 12, # 14) # 5, # 7, # 9, # 11, # 13, it is possible to # 15) constituting the 2 ^nd to the ECCE. Based on this, the ECCE indexing method in the corresponding EPDCCH set is also the same as the above-mentioned N = 4 for each ECCE / EREG mapping method, from a 1 ^st ECCE constructed in a PRB pair having the lowest PRB index to a PRB pair , ECCE # 1, .., ECCE # (2M-1) up to the 2 ^nd ECCE constituted by the ECCE # 0, ECCE # 1,.

10 is a flowchart illustrating a method of transmitting control information of a transmission / reception point according to an embodiment of the present invention.

Referring to FIG. 10, a transmission / reception point for transmitting control information to a terminal through a data area of a pair of resource blocks (PRB pair) of a subframe repeats 16 numbers in a resource block pair, (EREG) composed of resource elements having the same index with respect to the resource elements (REs) assigned to the resource elements (RE) (ECCE) are allocated to the resource element groups corresponding to the same index in step S910.

An example of an index assigned to a resource block pair (PRB pair) may be described with reference to FIGS. 3 to 8 above. Referring to FIG. 3 and FIG. 6, the EREG is indexed in a frequency-preferential manner from 0 to 15. In the embodiment shown in FIG. 3, the index 12 of the second symbol is indexed at the index 11 of the first symbol by indexing with the symbol-based cyclic shift. In the embodiment shown in FIG. 6, The index 12 of the first symbol is not indexed adjacent to the index 11 of the first symbol.

The transmission / reception point can allocate ECCEs to EREGs whose remainders divided by 4 of the EREGs correspond to the same index or EREGs whose remainders divided by 2 correspond to the same index.

For example, EREGs # 0, # 4, # 8, and # 12 can constitute one ECCE, while EREGs # 1 and # 5, # 9 and # 13 to another ECCE, EREG # 2, # 6, # 10 and # 14 to another ECCE, EREG # 3, # 7, # 11 and # .

As another example, when EREGs # 0, # 2, # 4, # 6, # 8, # 10, # 12, # 14 are allocated to EREGs ECCE can be configured and EREGs # 1, # 3, # 5, # 7, # 9, # 11, # 13 and # 15 can constitute another ECCE.

The transmission / reception point transmits control information to the terminal through at least one control channel element of the control channel elements (S920).

The control information may be transmitted through the EPDCCH, which is a control channel transmitted in the data area 220, and the EPDCCH is allocated to the at least one control channel element in a pair of resource blocks.

The resource block pair to which the control information is transmitted may be one PRB of an EPDCCH set composed of M PRB groups. Depending on the EPDCCH transmission type, the EPDCCH set may be a localized type or a distributed type, where X is 1 or 2 ⁿ (n = 1, 2, 3, 4 , 5).

The resource block pair to which control information is transmitted may form one downlink EPDCCH set in a centralized manner with another one or more resource block pairs.

11 is a flowchart illustrating a method of receiving control information of a UE according to another embodiment of the present invention.

Referring to FIG. 11, a terminal receiving control information from a transmission / reception point through a data area of a physical resource block pair of a subframe repeats 16 numbers in a frequency block in a resource block pair, The remainder divided by 4 of the resource elements constituted by the resource elements having the same index with respect to the Resource Elements is allocated to the resource element groups corresponding to the same index or the remainder obtained by dividing by 2 is the same The wireless signal is received through at least one control channel element among the control channel elements assigned to the resource element groups corresponding to the index (S1010). Then, the terminal can acquire the control information from the received radio signal (S1020).

An example of an index assigned to a resource block pair (PRB pair) may be described with reference to FIGS. 3 to 8 above. Referring to FIG. 3 and FIG. 6, the EREG is indexed in a frequency-preferential manner from 0 to 15. In the embodiment shown in FIG. 3, the index 12 of the second symbol is indexed at the index 11 of the first symbol by indexing with the symbol-based cyclic shift. In the embodiment shown in FIG. 6, The index 12 of the first symbol is not indexed adjacent to the index 11 of the first symbol.

The transmission / reception point can allocate ECCEs to EREGs whose remainders divided by 4 of the EREGs correspond to the same index or EREGs whose remainders divided by 2 correspond to the same index.

For example, EREGs # 0, # 4, # 8, and # 12 can constitute one ECCE, while EREGs # 1 and # 5, # 9 and # 13 to another ECCE, EREG # 2, # 6, # 10 and # 14 to another ECCE, EREG # 3, # 7, # 11 and # .

As another example, when EREGs # 0, # 2, # 4, # 6, # 8, # 10, # 12, # 14 are allocated to EREGs ECCE can be configured and EREGs # 1, # 3, # 5, # 7, # 9, # 11, # 13 and # 15 can constitute another ECCE.

12 is a diagram illustrating a configuration of a transmission / reception point according to another embodiment of the present invention.

Referring to FIG. 12, a transmission / reception point 1100 for transmitting control information to a terminal through a data area of a physical resource block pair of a subframe includes a control unit 1110, a transmission unit 1120, a reception unit 1130, And the like.

The control unit 1110 repeats the 16 numbers in the resource block pair in the frequency priority order, and selects one of the resource elements (resource elements) having the same index with respect to the indexed resource elements Allocates the control channel elements to the resource element groups corresponding to the same index or the resource element groups corresponding to the same index with the remainder divided by two.

Herein, the resource block pair may constitute a set of one enhanced physical downlink control channel in a localized manner with one or more other resource block pairs. The indexes of the resource element groups allocated to the control channel elements are {0, 4, 8, 12}, {1,5,9,13}, {2,6,10,14} , 11,15} or {0, 2, 4, 6, 8, 10, 12, 14} and {1,3,5,7,9,11,13, 15} respectively.

In addition, the controller 1220 controls the ECCE / EREG mapping method for transmitting the EPDCCH and the overall transmission / reception point operation according to the ECCE indexing in any centralized EPDCCH set necessary for carrying out the present invention described above.

Transmitter 1120 transmits control information to the terminal through at least one control channel element of the control channel elements.

The transmitting unit 1120 and the receiving unit 1030 are used to transmit and receive signals, messages, data, and information necessary for performing the above-described present invention to and from the terminal.

13 is a diagram illustrating a configuration of a UE according to another embodiment of the present invention.

13, a terminal 1200 receiving control information from a transmission / reception point through a data area of a physical resource block pair of a subframe includes a receiver 1210, a controller 1220, a transmitter 1230, And the like.

The receiving unit 1210 repeats 16 numbers in the resource block pair in the frequency priority order, and selects one of the resource element groups (Resource Resource Groups) having the same index with respect to the indexed resource elements To the resource element groups corresponding to the same index or a remainder divided by two receives radio signals through at least one of the control channel elements assigned to the resource element groups corresponding to the same index do.

Herein, the resource block pair may constitute a set of one enhanced physical downlink control channel in a localized manner with one or more other resource block pairs. Also, the indices of the resource element groups assigned to the control channel elements are {0, 4, 8, 12}, {1,5,9,13}, {2,6,10,14} , 11,15} or {0, 2, 4, 6, 8, 10, 12, 14} and {1,3,5,7,9,11,13,15} respectively.

The control unit 1220 acquires the control information from the radio signal received by the receiving unit 1210. The control unit 1220 controls the ECCE / EREG mapping method for EPDCCH reception and the overall operation of the UE according to the ECCE indexing in any convergence type EPDCCH set necessary for carrying out the present invention described above.

The transmitting unit 1230 and the receiving unit 1210 are used to transmit and receive signals, messages, data and information necessary for carrying out the present invention to and from the transmitting and receiving point.

The contents related to the standard specification mentioned in the above-mentioned embodiments are omitted for the sake of brevity and constitute a part of this specification. Therefore, it is to be understood that the content of some of the contents related to the above standard is added to or included in the scope of the present invention.

The following documents specifically attached form part of this specification as part of the already published documents. Therefore, it is to be understood that the content of the above standard content and portions of the standard documents are added to or contained in the scope of the present invention.

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 (16)

A control information transmission method of a transmission / reception point for transmitting control information to a terminal through a data area of a physical resource block pair of a subframe,
(2) out of the enhanced resource element groups composed of the resource elements having the same index with respect to resource elements (resource elements) indexed by repeating 16 numbers in one resource block pair in frequency priority Allocating control channel elements to N resource element groups corresponding to the same resource element group index; And
And transmitting control information to the terminal through at least one control channel element of the control channel elements,
The resource block pair constitutes a set of one physical downlink control channel in a localized manner with one or more other resource block pairs,
The N is determined based on the subframe type and the cyclic prefix length,
A normal subframe corresponding to an extended cyclic prefix, a special subframe 1, 2, 3, 5, 6 corresponding to an extended cyclic prefix and a normal cyclic prefix corresponding to an extended cyclic prefix And N is 8 in the case of the corresponding special subframe 1, 2, 6, 7, 9.
delete delete The method according to claim 1,
The index group of N resource element groups corresponding to each of the control channel elements is {0,2,4,6,8,10,12,14} and {1,3,5,7,9,11 , 13,15}. ≪ / RTI >
A control information reception method of a terminal that receives control information from a transmission / reception point through a data area of a pair of resource blocks of a subframe (Physical Resource Block pair)
(2) out of the enhanced resource element groups composed of the resource elements having the same index with respect to resource elements (resource elements) indexed by repeating 16 numbers in one resource block pair in frequency priority Receiving a radio signal through at least one control channel element among control channel elements assigned to N resource element groups corresponding to the same resource element group index; And
And obtaining the control information from the wireless signal,
The resource block pair constitutes a set of one physical downlink control channel in a localized manner with one or more other resource block pairs,
The N is determined based on the subframe type and the cyclic prefix length,
A normal subframe corresponding to an extended cyclic prefix, a special subframe 1, 2, 3, 5, 6 corresponding to an extended cyclic prefix and a normal cyclic prefix corresponding to an extended cyclic prefix And N is 8 in the case of the corresponding special subframe 1, 2, 6, 7, 9.
delete delete 6. The method of claim 5,
The index group of N resource element groups corresponding to each of the control channel elements is {0,2,4,6,8,10,12,14} and {1,3,5,7,9,11 , 13,15}. ≪ / RTI >
A transmission / reception point for transmitting control information to a terminal through a data area of a physical resource block pair of a subframe,
(2) out of the enhanced resource element groups composed of the resource elements having the same index with respect to resource elements (resource elements) indexed by repeating 16 numbers in one resource block pair in frequency priority A control unit for allocating control channel elements to N resource element groups corresponding to the same resource element group index; And
And a transmitter for transmitting control information to the terminal through at least one control channel element of the control channel elements,
The resource block pair constitutes a set of one physical downlink control channel in a localized manner with one or more other resource block pairs,
The N is determined based on the subframe type and the cyclic prefix length,
A normal subframe corresponding to an extended cyclic prefix, a special subframe 1, 2, 3, 5, 6 corresponding to an extended cyclic prefix and a normal cyclic prefix corresponding to an extended cyclic prefix And N is 8 in the case of the corresponding special subframe 1, 2, 6, 7, 9.
delete delete 10. The method of claim 9,
The index group of N resource element groups corresponding to each of the control channel elements is {0,2,4,6,8,10,12,14} and {1,3,5,7,9,11 , 13,15}. ≪ / RTI > To a terminal that receives control information from a transmission / reception point through a data area of a physical resource block pair of a subframe,
(2) out of the enhanced resource element groups composed of the resource elements having the same index with respect to resource elements (resource elements) indexed by repeating 16 numbers in one resource block pair in frequency priority A receiving unit for receiving a radio signal through at least one control channel element among control channel elements allocated to N resource element groups corresponding to the same resource element group index; And
And a control unit for obtaining the control information from the radio signal,
The resource block pair constitutes a set of one physical downlink control channel in a localized manner with one or more other resource block pairs,
The N is determined based on the subframe type and the cyclic prefix length,
A normal subframe corresponding to an extended cyclic prefix, a special subframe 1, 2, 3, 5, 6 corresponding to an extended cyclic prefix and a normal cyclic prefix corresponding to an extended cyclic prefix And N is 8 for corresponding special subframes 1, 2, 6, 7, and 9. delete delete 14. The method of claim 13,
The index group of N resource element groups corresponding to each of the control channel elements is {0,2,4,6,8,10,12,14} and {1,3,5,7,9,11 , 13,15}.

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