KR20130076456A - Method and apparatus for transmitting and receiving control information in wireless communication system - Google Patents

Abstract

PURPOSE: A method and a device for transmitting and receiving control information in a wireless communication system are provided to transmit more control information by performing a control channel transmission using an existing data region. CONSTITUTION: A base station (1500) includes a control unit (1510), a memory (1520), and an RF unit (1530). The RF unit receives an enhanced physical downlink control channel (ePDCCH). The control unit obtains the necessary information from the received ePDCCH. The control unit divides the resource blocks mapped on the ePDCCH and generates a modulated symbol by de-interleaving the received sub blocks. [Reference numerals] (1510) Control unit; (1520) Memory; (1530) RF unit; (1540) Distribution mapping unit; (1550) Control information setting unit

Description

Method and apparatus for transmitting and receiving control information in wireless communication system TECHNICAL FIELD

The present invention relates to wireless communication technology, and more particularly, to a method and apparatus for distributed transmission of a control channel in a conventional data area in downlink transmission.

In a wireless communication system, channel information and system synchronization need to be acquired for effective data transmission / reception. For example, in a wireless communication system environment, fading occurs due to a path delay. On the receiving side, the signal transmitted from the transmitting side can be accurately restored by compensating for the signal distortion due to the fading.

Meanwhile, in addition to the data transmission / reception scheme using one transmission antenna and one reception antenna to increase the performance and communication capacity of the wireless communication system, the data transmission and reception efficiency using a plurality of antennas may be increased in a specific range. The method can be used.

As the amount of data transmission increases, the amount of control information related to data transmission also increases. Although the amount of transmission of control information is increasing, a control channel for transmitting control information is operating in a limited manner. For example, the downlink control channel is transmitted at the beginning of each subframe and is only detected based on a cell specific reference signal.

Therefore, there is a discussion about how to efficiently use a limited transmission area of control information or how to further secure a transmission area of control information on a transmission channel. In addition, if the transmission area of the control information is further secured on the transmission channel, it may be a problem how the allocation of the transmission resource and the resource mapping for the transmission of the control information can be made.

An object of the present invention is to provide a method and apparatus for effectively transmitting downlink control information.

An object of the present invention is to provide a method and apparatus for transmitting downlink control information in a conventional data area.

An object of the present invention is to provide a method and apparatus for distributed transmission of a control channel in a data region in the transmission of a control channel allocated to a conventional data region.

An object of the present invention is to provide a method and apparatus for transmitting a control channel allocated to a data area in predetermined units.

An object of the present invention is to provide a method and apparatus for defining a distribution unit of a control channel allocated to a data area according to a resource structure based on DMRS and transmitting control information using the same.

 (1) An embodiment of the present invention provides a method for controlling a test subject, comprising: de-interleaving a received ePDCCH region, demodulating a deinterleaved modulation symbol, and decoding a demodulated symbol. In the deinterleaving step, the interblock mapped to the ePDCCH is deinterleaved, and the subblock is divided into a predetermined number of resource blocks allocated to the ePDCCH.

 (2) In (1), the deinterleaving may be performed between a plurality of resource blocks allocated to the ePDCCH region.

 (3) In (1), the number of subblocks per resource block may be equal to the number of resource blocks allocated for the ePDCCH transmission.

 (4) In (3), the deinterleaved subblocks can be received distributed among different resource blocks.

(5) In (1), the sub block is obtained by dividing a resource block allocated to the ePDCCH in OFDM symbol units and may include a resource element that does not transmit a reference signal among resource elements belonging to the OFDM symbol. have.

(6) In (5), in the deinterleaving step, deinterleaving is performed on subblocks mapped to the same ePDCCH among subblocks belonging to different resource blocks, and the subblocks mapped to the same ePDCCH are Depending on the resource block, they may belong to different OFDM symbols.

(7) In (1), the sub block is obtained by dividing a resource block allocated to the ePDCCH in subcarrier units, and includes a resource element that does not transmit a reference signal among resource elements belonging to the subcarrier. Can be.

(8) In (7), in the deinterleaving step, deinterleaving is performed on subblocks mapped to the same ePDCCH among subblocks belonging to different resource blocks, and the subblock mapped to the same ePDCCH. They may belong to different subcarriers according to resource blocks.

 (9) Another embodiment of the present invention is a method of transmitting control information, comprising: mapping an ePDCCH to be transmitted to a resource block and performing interleaving on the resource block to which the ePDCCH is mapped. An ePDCCH-mapped resource block may be divided into subblocks and interleaved.

 (10) In (9), the interleaving may be performed between a plurality of resource blocks allocated to the ePDCCH region.

 (11) In (9), the number of subblocks per resource block may be equal to the number of resource blocks allocated to the ePDCCH transmission.

 (12) In (11), the subblocks can be transmitted by being distributed to different resource blocks by the interleaving.

 (13) In (9), the subblock is obtained by dividing a resource block allocated to the ePDCCH in OFDM symbol units and may include a resource element that does not transmit a reference signal among resource elements belonging to the OFDM symbol. have.

 (14) In (13), in the interleaving step, interleaving is performed to distribute subblocks mapped to the same ePDCCH to different resource blocks, and subblocks mapped to the same ePDCCH are different OFDM by the interleaving. Can belong to a symbol.

 (15) In (9), the sub block is obtained by dividing a resource block allocated to the ePDCCH in subcarrier units, and includes a resource element that does not transmit a reference signal among resource elements belonging to the subcarrier. Can be.

 (16) In (15), in the interleaving step, interleaving is performed to distribute subblocks mapped to the same ePDCCH to different resource blocks, and subblocks mapped to the same ePDCCH are different subcarriers by the interleaving. Can belong to.

 (17) Another embodiment of the present invention is a control information receiving apparatus, comprising: an RF unit for receiving an ePDCCH and a controller for obtaining necessary information from the received ePDCCH, wherein the controller divides a resource block mapped to the ePDCCH. The decoded received subblocks may be deinterleaved to generate a modulation symbol.

 (18) Another embodiment of the present invention is a control information transmission apparatus, comprising: an RF unit for transmitting an ePDCCH and a control unit for interleaving a resource block to which the ePDCCH is to be transmitted, wherein the control unit is a resource to which the ePDCCH is mapped. A block may be divided into subblocks and interleaved.

According to the present invention, more control information can be transmitted by performing control channel transmission using a conventional data area.

According to the present invention, the frequency gain can be increased by distributing and transmitting the control channel allocated to the data region in subcarrier units.

According to the present invention, by distributing and transmitting control channels allocated to conventional data regions, transmission errors can be distributed and transmission efficiency can be improved.

According to the present invention, the resource can be efficiently used by defining the distributed transmission unit of the control channel to match the resource structure based on the DMRS.

1 is a flowchart schematically illustrating a method of configuring a PDCCH.
2 schematically illustrates an example of resource mapping of a PDCCH.
3 is a diagram schematically illustrating an example of R-PDCCH transmission.
4 schematically illustrates an example of a subframe to which an ePDCCH is allocated.
5 schematically illustrates an example in which ePDCCH is distributed mapped over each eRB according to the present invention.
6 schematically illustrates eREGs defined based on an OFDM symbol, in accordance with the present invention.
7 is a diagram schematically illustrating distribution mapping of an ePDCCH using an eREG according to the present invention.
8 is a diagram schematically illustrating an example in which ePDCCH is distributed mapped by eREG according to the present invention.
9 schematically illustrates eREGs defined based on a subcarrier according to the present invention.
FIG. 10 is a diagram schematically illustrating distribution mapping of an ePDCCH using an eREG according to the present invention.
FIG. 11 schematically illustrates a subframe structure for a case in which a PDCCH and a CRS do not exist, such as an extended carrier or MBSFN.
12 schematically illustrates an eREG defined when using an OCC of length 2 in accordance with the present invention.
13 is a flowchart schematically illustrating an operation of a terminal for obtaining control information from an ePDCCH in a system according to the present invention.
14 is a flowchart schematically illustrating an operation of a base station for distributed transmission of an ePDCCH in a system to which the present invention is applied.
15 is a block diagram schematically illustrating a configuration of a base station in a system to which the present invention is applied.
16 is a block diagram schematically illustrating a configuration of a terminal in a system to which the present invention is applied.

Hereinafter, some embodiments will be described in detail with reference to the accompanying 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 symbols as possible even if they are shown in different drawings. In addition, in describing the embodiments of the present specification, when it is determined that the detailed description of the related well-known configuration or function may obscure the subject matter of the present specification, the detailed description thereof will be omitted.

The present specification describes a wireless communication network, and the work performed in the wireless communication network is performed in the process of controlling the network and transmitting data in a system (for example, a base station) that manages the wireless communication network, or the corresponding wireless network. Work can be done in the terminal coupled to.

A user equipment (UE) may be fixed or mobile, and may include a mobile station (MS), a mobile terminal (MT), a user terminal (UT), a subscriber station (SS), a wireless device, and a personal digital assistant (PDA). It may be called other terms such as digital assistant, wireless modem, handheld device.

A base station generally refers to a fixed station that communicates with a terminal and may be referred to by other terms such as an evolved-NodeB (eNB), a base transceiver system (BTS), an access point, and the like.

Each base station provides communication services for a particular geographic area (commonly called a cell). The cell may again be divided into multiple regions (referred to as sectors). In addition, multiple transmission terminals may configure one cell.

A downlink radio frame of 3GPP LTE is composed of 20 slots (# 0 to # 19). One subframe consists of two slots. The time (length) of transmitting one subframe is called a transmission time interval (TTI). The length of one subframe may be 1 ms, for example, and the length of one slot may be 0.5 ms, for example.

One slot may include a plurality of symbols in the time domain. For example, in the case of 3GPP LTE using Orthogonal Frequency Division Multiple Access (OFDMA) in downlink (DL), the symbol may be an Orthogonal Frequency Division Multiplexing (OFDM) symbol. Meanwhile, the representation of the symbol period in the time domain is not limited by the multiple access scheme or the name.

The number of OFDM symbols included in one slot may vary depending on the length of a cyclic prefix (CP). For example, one slot may include 7 OFDM symbols in the case of a normal CP, and one slot may include 6 OFDM symbols in the case of an extended CP.

A resource block (RB) is a resource allocation unit and may include a plurality of subcarriers in one slot. For example, if one slot includes 7 OFDM symbols in the time domain and the resource block includes 12 subcarriers in the frequency domain, one resource block may contain 7 ㅧ 12 resource elements (REs). It may include.

According to the existing definition, the downlink subframe may be divided into a control region and a data region in the time domain. The control region may include up to four OFDM symbols in front of the first slot in the subframe. The number of OFDM symbols included in the control region may be changed. A control channel such as PDCCH is allocated to the control region, and a data transmission channel such as PDSCH is allocated to the data region.

The Physical Control Format Indicator Channel (PCFICH) transmitted in the first OFDM symbol of a subframe is a Control Format Indicator (CFI) indicating the number of OFDM symbols (that is, the size of the control region) used for transmission of control channels in the subframe. Carry) For example, the terminal may first receive the CFI on the PCFICH and then monitor the PDCCH. The PCFICH is transmitted using fixed PCFICH resources of a subframe without using blind decoding.

Control information transmitted through the PDCCH is called downlink control information (DCI). DCI is the resource allocation of PDSCH (also called DL grant), the PUSCH resource allocation (also called UL grant), and a set of transmit power control commands for individual UEs in any UE group. And / or information about activation of Voice over Internet Protocol (VoIP).

1 is a flowchart schematically illustrating a method of configuring a PDCCH. After determining the PDCCH format according to the DCI transmitted to the UE, the base station attaches a cyclic redundancy check (CRC) to the corresponding DCI, and is called a unique identifier (RNTI (Radio Network Temporary Identifier) according to the owner of the PDCCH or the purpose of the PDCCH). Scrambling to the CRC (S110).

When the corresponding PDCCH is a PDCCH for a specific UE, a unique identifier of the UE, for example, a C-RNTI (Cell-RNTI), may be scrambled in the CRC. If the corresponding PDCCH is a PDCCH for a paging message, a paging indication identifier, for example, P-RNTI (P-RNTI), may be scrambled in the CRC. If the corresponding PDCCH is a PDCCH for system information, a system information identifier, for example, a System Information-RNTI (SI-RNTI), may be scrambled in the CRC. In addition, a random access-RNTI (RA-RNTI) may be scrambled in the CRC to indicate a random access response that is a response to the transmission of the random access preamble of the UE.

When the C-RNTI is used, the PDCCH carries control information for the corresponding specific UE (called UE-specific control information), and when another RNTI is used, the PDCCH is received by all or a plurality of terminals in the cell. It carries common control information (this is called cell specific control information).

The DCI to which the CRC is added is encoded to generate coded data (S120). Here, the encoding may include channel encoding and rate matching.

The encoded data is modulated to generate modulation symbols (S130). Subsequently, modulation symbols are mapped to resource elements (REs) (S140).

2 schematically illustrates an example of resource mapping of a PDCCH.

In a multi-antenna system, R0 is a reference signal of the first antenna, R1 is a reference signal of the second antenna, R2 is a reference signal of the third antenna, and R3 is a reference signal of the fourth antenna.

The control region in the subframe includes a plurality of control channel elements (CCEs). The CCE is a logical allocation unit used to provide a coding rate according to the state of a radio channel to a PDCCH and corresponds to a plurality of resource element groups (REGs). The format of the PDCCH and the number of bits of the PDCCH are determined according to the correlation between the number of CCEs and the coding rate provided by the CCEs.

A predetermined number of REs may be aggregated to form a REG, and a predetermined number of REGs may be aggregated to configure a CCE. {1, 2, 4, 8} CCEs may be used to configure one PDCCH, and each element in the set {1, 2, 4, 8} is called a CCE aggregation level.

It is possible to interleave a control channel consisting of one or more CCEs. The unit of interleaving may be REG. The interleaved control channel may be mapped to a physical resource after performing a cyclic shift based on a cell identifier. Alternatively, the control channel may be interleaved after being mapped to a physical resource.

In 3GPP LTE, blind decoding is used to detect the PDCCH. Blind decoding is also referred to as blind detection. Blind decoding is a method of descrambling a desired identifier to a CRC of a received PDCCH (called a candidate PDCCH) and checking a CRC error to determine whether the corresponding PDCCH is its control channel or not. to be. In this case, the blind detection PDCCH may include an ePDCCH described later.

In the present specification, 'RE' (Resource Element) represents the smallest frequency-time unit to which a modulation symbol of a data channel or a modulation symbol of a control channel is mapped. If there are M subcarriers on one OFDM symbol, and one slot includes N OFDM symbols, one slot includes M × N REs.

In addition, in the present specification, 'PRB' (Physical Resource Block) represents a unit frequency-time resource for transmitting data. One PRB is composed of a plurality of REs consecutive in the frequency-time domain, and a plurality of PRBs are defined in one subframe. The PRB may be the RB described above.

Meanwhile, a reference signal (RS) known to each other is used by the transceiver for channel estimation or channel state measurement.

Since the receiver knows the information of the reference signal, the receiver can estimate the channel based on the reference signal of the received signal and compensate the channel value to accurately obtain the data sent from the transmitter.

Reference signals are generally transmitted in sequence. The reference signal sequence may use a PSK-based computer generated sequence (PSK) -based computer. Examples of PSKs include Binary Phase Shift Keying (BPSK) and Quadrature Phase Shift Keying (QPSK). Alternatively, the reference signal sequence may use a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence. Examples of the CAZAC sequence include a ZC-based sequence, a ZC sequence with a cyclic extension, a truncation ZC sequence (ZC sequence with truncation), and the like . Alternatively, the reference signal sequence may use a PN (pseudo-random) sequence. Examples of PN sequences include m-sequences, computer generated sequences, Gold sequences, and Kasami sequences. Also, the reference signal sequence may use a cyclically shifted sequence.

The downlink reference signal includes a cell-specific RS (CRS), a Multimedia Broadcast and Multicast Single Frequency Network (MBSFN) reference signal, a UE-specific RS, and a positioning reference signal (PRS). RS and Channel State Information (CSI) reference signals (CSI-RS).

In a multi-antenna system, resource elements used for reference signals of one antenna are not used for reference signals of other antennas. To avoid interference between antennas.

The CRS is a reference signal transmitted to all terminals in a cell and used for channel estimation. The CRS may be transmitted in all downlink subframes in a cell supporting PDSCH transmission.

The MBSFN reference signal is a reference signal for providing a multimedia broadcast multicast service (MBMS) and may be transmitted in a subframe allocated for MBSFN transmission. The MBSFN reference signal may be defined in an extended CP structure.

The PRS may be used for location measurement of the terminal. The PRS may be transmitted only through resource blocks in a downlink subframe allocated for PRS transmission.

CSI-RS may be used for estimation of channel state information. The CSI-RS may be relatively sparse in the frequency domain or the time domain and may be punctured in the data region of the general subframe or the MBSFN subframe. A channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), and the like may be reported from the terminal when necessary through the estimation of the CSI.

 The UE-specific reference signal is a reference signal received by a specific terminal or a specific terminal group in a cell, and is mainly used for data demodulation of a specific terminal or a specific terminal group, and thus may be referred to as DMRS.

The location of the frequency domain and the location of the time domain in the subframe of DMRS may be determined according to a resource block allocated for PDSCH transmission. The DMRS sequence may be determined according to the terminal ID, and only a specific terminal corresponding to the terminal ID may receive the DMRS. The DMRS sequence may be generated for each subframe and applied in units of OFDM symbols.

CRS can be used simultaneously with DMRS. For example, CRS may be used in an area where control information in a subframe is transmitted, and CRS and DMRS may be used in other areas. In this case, the CRS and the DMRS may be located in different subcarriers and / or different OFDM symbols.

The base station may improve the performance of channel estimation by reducing the interference of the reference signal received from the adjacent cell at the receiver by multiplying the predefined sequence by the cell-specific downlink reference signal. The predefined sequence may be any one of a PN sequence, an m-sequence, a Walsh hadamard sequence, a ZC sequence, a GCL sequence, a CAZAC sequence, and the like. The predefined sequence may be applied in units of OFDM symbols in one subframe, and another sequence may be applied according to a cell ID, a subframe number, an OFDM symbol position, a terminal ID, and the like.

Meanwhile, in the conventional 3GPP LTE, the PDCCH, which is a downlink control signal channel, is transmitted only in the control region located in front of each subframe, and the PDCCH is detected based on the CRS. Therefore, the number of PDCCHs that can be transmitted was limited. Recently, in consideration of using CoMP (Cooperative Multi Point), Multi User-Multi Input Multi Output (MU-MIMO), and Carrier Aggregation (CA) to increase data transmission rate and transmission rate, It is difficult to sufficiently transmit a control signal with limited PDCCH resources. In order to solve this problem, it may be considered to transmit an Enhanced PDCCH (EPDCCH) in a data region based on a UE-specific DMRS.

In case of PDCCH transmission based on CRS, a reference signal CRS is added after precoding is performed for each stream. Accordingly, in the CRS-based transmission, the UE may recognize the physical antenna ports # 0 to # t-1, and information about precoding should be transmitted to the UE.

In case of transmitting a PDCCH based on DMRS, a reference signal DMRS is added before precoding each stream. Accordingly, the DMRS is also precoded with each stream, and the DMRS has information about precoding. The UE may recognize a virtual antenna port, that is, streams (# 0 to # k-1), and in case of demodulating based on the information possessed by the DMRS, precoding information for demodulation is separately transmitted to the UE. There is no need to transfer. In this case, the UE may use the DMRS for demodulation and use the CSI-RS for measurement.

As an example of transmitting a control signal based on DMRS, there is a physical downlink control channel (R-PDCCH) for a relay. The R-PDCCH delivers downlink control information (DCI) for the relay node. For example, resources for downlink and / or uplink base station-relay link (Un link) data may be allocated through the R-PDCCH.

3 is a diagram schematically illustrating an example of R-PDCCH transmission. Referring to FIG. 3, in the time domain, transmission of the R-PDCCH is performed in a data region of a downlink subframe. In the frequency domain, the transmission of the R-PDCCH occurs in a set of semi-statically allocated resource blocks. From a latency point of view, it is desirable to place the transmission on downlink allocation in front of time within a subframe. Therefore, in the subframe, the R-PDCCH for downlink allocation may be transmitted before the R-PDCCH for uplink grant.

In the case of R-PDCCH, it is used to transfer control information for a relay node. When transmitting the R-PDCCH, based on DMRS, the R-PDCCH is transmitted locally. In other words, REs for transmitting one EPDCCH belong to only one RB. In addition, if the R-PDCCH is distributed and transmitted, the R-PDCCH is still transmitted based on the CRS. In transmitting the R-PDCCH, REG level interleaving based on CCE may be used, which may be regarded as the same as the distributed transmission of the PDCCH.

In distributed transmission of PDCCH and R-PDCCH, the aggregation level is based on CCE as described above, and interleaving is based on REG. Here, the REG may be defined based on the CRS.

Resource-Element Groups (REGs) are used to define mappings of control channels to REs.

REG may be represented by an index pair (p ', q') of the lowest p index among all REs in the group having the same q value. The set of REs (p, q) in the REG depends on the number of cell specific reference signals (CRS). Regarding the number of ^DL resource blocks N ^DL _RB , the index n _PRB specifying the _PRB , the number of subcarriers in the resource block N ^RB _sc , the relationship of p ₀ = n _{PRB ·} N ^RB _sc and 0 ≦ n _PRB ≤N ^DL _RB Is established.

In the first OFDM symbol of the first slot in the subframe, the two REGs in PRB (n _PRB ) consist of REs (p, q = 0). At this time, p is p = p ₀ + 0, p ₀ + 1,... , p ₀ +5 and p = p ₀ +6, p ₀ +7,... , p ₀ +11.

In the case where one or two cell specific reference signals (CRS) are configured, in the second OFDM symbol of the first slot in the subframe, three REGs in the PRB (n _PRB ) are composed of REs (p, q = 1). . At this time, p is p = p ₀ + 0, p ₀ + 1,... , p ₀ +3, p = p ₀ +4, p ₀ +5,... , p ₀ +7 and p = p ₀ +8, p ₀ +9,... , p ₀ +11.

When four cell specific reference signals (CRS) are configured, in the second OFDM symbol of the first slot in the subframe, two REGs in the PRB (n _PRB ) are composed of REs (p, q = 1). At this time, p is p = p ₀ + 0, p ₀ + 1,... , p ₀ +5 and p = p ₀ +6, p ₀ +7,... , p ₀ +11.

In the third OFDM symbol of the first slot in the subframe, three REGs in PRB (n _PRB ) are composed of REs (p, q = 2). At this time, p is p = p ₀ + 0, p ₀ + 1,... , p ₀ +3, p = p ₀ +4, p ₀ +5,... , p ₀ +7, and p = p ₀ +8, p ₀ +9,... , p ₀ +11.

In the case of a normal cyclic prefix (CP), in the fourth OFDM symbol of the first slot in the subframe, three REGs in the PRB (n _PRB ) are composed of REs (p, q = 3). At this time, p is p = p ₀ + 0, p ₀ + 1,... , p ₀ +3, p = p ₀ +4, p ₀ +5,... , p ₀ +7, and p = p ₀ +8, p ₀ +9,... , p ₀ +11.

In the case of an extended CP, in the fourth OFDM symbol of the first slot in the subframe, two REGs in the PRB (n _PRB ) are composed of REs (p, q = 3). At this time, p is p = p ₀ + 0, p ₀ + 1,... , p ₀ +5 and p = p ₀ +6, p ₀ +7,... , p ₀ +11.

Meanwhile, as a control channel for transmitting control information in a conventional data region, an ePDCCH (enhanced PDCCH) for transmitting control information for a terminal may be considered. The ePDCCH may also be distributed and transmitted locally or may be transmitted locally. However, unlike the R-PDCCH, the ePDCCH is used to transmit control information for the UE, and both cases of distributed transmission and local transmission may be performed based on DMRS.

Distributed transmission of the ePDCCH may be optimized for a PRB pair structure unlike the R-PDCCH. In the case of R-PDCCH, since the REG to which the R-PDCCH is mapped is defined based on the CRS structure when distributed transmission, it is difficult to effectively use the RE, and it is difficult to obtain sufficient gain in frequency diversity. .

By distributing and transmitting the ePDCCH based on DMRS, it is possible to prevent waste of resources (RE). This is because a full match can be obtained between the ePDCCHs to be transmitted and the structure of a PRB pair based on DMRS. In addition, when distributed transmission of the ePDCCH based on DMRS, a full gain of frequency diversity may be obtained in the ePDCCH region.

Hereinafter, with reference to the drawings will be described in terms of distributed transmission of the ePDCCH based on DMRS.

In order to distribute and transmit the ePDCCH, interleaving may be performed on a transmission resource to which the ePDCCH is mapped. In the conventional case, the length of the interleaving was fixed at 32. In the case of interleaving according to the invention, the length of the interleaving may be adaptively determined in order to match the structure of the PRB pair. In other words, the length of interleaving may be determined by the total number of PRB pairs in the resource allocation. For example, if K PRB pairs are included in the resource allocation (RA) for the ePDCCH region, the length of interleaving may be K.

The following three units can be considered as a unit for performing interleaving.

(1) Interleaving of bits, modulation symbols, or REG levels

(2) Interleaving at 1 / N PRB Pair Level

(3) eREG based interleaving

First, the case of interleaving at the bit, modulation symbol, or REG level will be described. In this case, inputs that are units of interleaving are defined as d ₀ ⁽ⁱ⁾ ,... Let dd _-1 ⁽ⁱ⁾ be. d may be a bit, a modulated symbol or REG, and D represents the number of inputs.

The operation of an interleaver can be represented by an interleaving matrix, where the number of columns in the interleaving matrix is fixed to 32, and a vector A having elements by the number of rows and a vector B having elements by the number of columns The minimum number of rows ≤ (AXB) may be determined as the number of rows of the interleaving matrix.

Subsequently, the interleaving matrix is filled with a sequence of inputs, and then inter-column permutation is applied to obtain an interleaved result.

In the present invention, each PRB pair to which the ePDCCH is mapped may be divided into predetermined resource blocks, and the divided resource blocks may be distributed. In other words, in the present invention, the ePDCCH can be distributed and distributed by distributing resource blocks to which ePDCCHs are mapped to the PRB pair. In this case, as a method for distributing the ePDCCH, an ePDCCH-mapped resource block may be interleaved at a 1 / N PRB level or an eREG may be interleaved at a level. In this case, the eREG may be an example of the predetermined resource block obtained by dividing a PRB pair.

Hereinafter, interleaving of 1 / N PRB level and interleaving of eREG level according to the present invention will be described in detail.

<Interleaving at 1 / N PRB Pair Level>

4 schematically illustrates an example of a subframe to which an ePDCCH is allocated. Referring to FIG. 4, the control region 400 transmits a PCFICH, a physical HARQ indicator channel (PHICH), and a PDCCH. The data region 410 is assigned an ePDCCH along with a PDSCH.

ePDCCH may be mapped in RB units. Therefore, resources to be used for the ePDCCH may be allocated in units of RBs. More specifically, as described above, the RB is defined in units of 12 slots, and includes 7 OFMD symbols and 12 subcarriers in the case of a normal CP, and 6 OFDM symbols and 12 in the case of an extended CP. Subcarriers are included. Therefore, one PRB pair may be defined for one subframe. Also in this embodiment illustrated in FIG. 4, the ePDCCH may be mapped to the remaining regions 420-1,..., 420 -K except for the control region 400 in the K PRB pairs allocated for transmission of the ePDCCH. have. Hereinafter, in the present specification, the "region remaining except for the control region in the PRB pair" is simply expressed as 'eRB' for convenience of description. Thus, "ePDCCH is mapped to the rest of the PRB pair except for the control region" may be expressed as "ePDCCH is mapped to the eRB."

Meanwhile, in FIG. 4, the ePDCCH1 is mapped to the second eRB 420-2 in the entire subframe, the ePDCCH is mapped to the third and fourth eRBs 420-3 and 420-4, and the K-th eRB ( 420- (K-1)) shows an example in which ePDCCH3 is mapped.

In the present invention, the ePDCCH mapped as shown in FIG. 4 may be distributed over the eRB. Through this, the transmission efficiency can be improved by distributedly transmitting the ePDCCH and increasing the frequency diversity gain.

According to the present embodiment, a method of interleaving performed at the subblock level of the eRB for distributed transmission of the ePDCCH will be described in detail as follows.

(1) Each eRB to which ePDCCH is mapped is divided into N subblocks

In the present embodiment, one eRB may be regarded as a kind of CCE. Therefore, in the present embodiment, the eRB may be referred to as an enhanced CCE (eCCE). The eRB to which the ePDCCH is mapped may be divided into N sub-blocks (N is an integer). The subblock SB _ij represents the jth subblock in the i th eRB allocated for the ePDCCH transmission (1 ≦ i ≦ K, 1 ≦ j ≦ N). In the present specification, 'ePDCCH-mapped transmission resources are distributed by interleaving' may be simply expressed as 'distributed mapping' for convenience of description.

If the number of symbols per eRB is N ^PRB _SYM , each subblock includes the number of OFDM symbols corresponding to one-Nth of N ^PRB _SYM . In this case, N is an integer, and 2, 4,... It can have a fixed value.

The N value may be determined such that each subblock may have an integer number of OFDM symbols. In addition, after determining the N value, the number of OFDM symbols of each subblock may be determined. For example, when the number of OFDM symbols per subblock, that is, the number of OFDM symbols per eRB divided by the number N of subblocks is not an integer (

), Subblock SB ₁ To SB _{N- 1} is

With N OFDM symbols, the last N th subblock SB _N is

It is possible to have two OFDM symbols.

N may be configured to be terminal specific. The N value may be set in consideration of the performance, state, network environment, channel environment, etc. of the terminal.

When the N value is set equal to the K value (N = K), full frequency gain can be obtained. Here, the case where the value of N is set equal to the number K of eRBs allocated for ePDCCH transmission will be described as an embodiment of the present invention.

(2) Number of columns of interleaving matrix C ^CC _subblock assignment

The number of columns of the matrix M _IL for interleaving may be set to the number of subblocks. Therefore, in the present embodiment, C ^CC _subblock = K may be set.

(3) Set the number of rows of the interleaving matrix R ^CC _subblock .

The number of rows of the matrix M _IL for interleaving may be set to the number of eRBs allocated for ePDCCH transmission.

(4) determine each element of the interleaving matrix

The matrix M _IL for interleaving may be represented by a matrix of R ^CC _subblocks X C ^CC _subblocks . Map the first subblock (BS ₁₁ ) of the first eRB to the position (1, 1) of the first row, the first column of the matrix M _IL , and the position of the first row (2, 1) of the second row of the matrix M _IL ) Fills the matrix M _IL row by row by mapping the second subblock BS ₁₂ of the first eRB. In other words, the j th subblock B _ij of the i th PRB pair is mapped to an element of the i th column (j, i) of the j th row of M _IL .

(5) The interleaving result using the interleaving matrix is output as a sequence of subblocks read out column by column. As a result, the ePDCCH is distributed over ePR within the same OFDM symbol.

5 schematically shows an example in which ePDCCH is distributed over each eRB according to the present invention.

As shown, control channels (PCFICH, PHICH, PDCCH) are mapped to the control region 500 of the subframe, and K eRBs 520-1, ..., 520- with PDSCH are mapped to the data region 510. E) is distributed mapped to K).

EPDCCH1 is mapped to the second subblock of each eRB 520-1, ..., 520-K, ePDCCH2 is mapped to the third and fourth subblocks, and ePDCCH3 is mapped to the N-1 th or K-1th subblocks. This mapped example is shown in FIG. 5.

On the other hand, without configuring the interleaving matrix based on the eRB to which the ePDCCH is mapped, based on the general subblock order, the j th subblock B _ij of the i th PRB pair is the i th column (j, i of the j th row of the matrix). After configuring an interleaving matrix mapped to elements of), it may be possible to apply the method to the ePDCCH allocation matrix. For example, in the case of FIG. 5, it may be considered that the allocation matrix of the ePDCCH is (0 ePDCCH1 ePDCCH2 ePDCCH2 ... ePDCCH3 0) ^T, and the interleaving matrix is applied thereto. Thus, the general allocation of ePDCCH (ePDCCH _k ) ^T (k = 1, 2,..., K) may also be applied to the interleaving matrix to distribute-map the ePDCCH over each PRB pair.

<eREG level interleaving>

In addition to the above-described method, a new REG may be defined to distribute (interleave) the resource to which the ePDCCH is mapped. In the present invention, the newly defined REG is referred to as eREG for convenience of description.

The general REG is defined based on the CRS as described above with respect to the PDCCH. However, in order to completely match the structure of the PRB pair based on the DMRS, an eREG based on the PRB pair may be newly defined.

In the present invention, one eREG may be defined for every OFEM symbol. In addition, in the present invention, one eREG may be defined for every subcarrier. The eREG defined for each OFEM symbol can be easily applied in the case of time division multiplexing (TDM). The eREG defined for each subcarrier can be easily applied in the case of frequency division multiplexing (FDM).

Hereinafter, an eREG defined for each OFDM symbol and an eREG defined for each subcarrier will be described.

EREG defined based on OFDM symbols

EREG defined based on an OFDM symbol: One eREG includes all REs belonging to the same OFDM symbol within one PRB. Here, RE is a RE that is not mapped to CRS and DMRS, and means RE used for transmission of ePDCCH.

6 schematically illustrates eREGs defined based on an OFDM symbol, in accordance with the present invention. As shown, in the subframe, the CRS and the DMRS are located according to each pattern. OFDM symbols may include CRS, may include DMRS, and may not include both CRS and DMRS. Accordingly, different eREGs may include different numbers of REs. Herein, the RE included in the eREG means an RE which is not mapped to the CRS and the DMRS as described above, and the ePDCCH is mapped to these REs.

Even when using an eREG, the transmission resource to which the ePDCCH is mapped may be distributed. In this case, the ePDCCH may be mapped for each eREG.

At this time, the distribution of the resource to which the ePDCCH is mapped may be performed through an interleaver, or may be performed through randomization that simply permutates the eREG. For convenience of description, unless otherwise mentioned in the present specification, 'interleaving' includes 'randomization' such as permutation.

In this embodiment, as an example of interleaving, dispersion by permutation will be described.

The distributed mapping method of ePDCCH by permutation is as follows:

(1) Permutation is performed between eRBs to which ePDCCH is mapped per OFDM symbol.

Let eREG corresponding to the k- th eRB and l- th OFDM symbol in a subframe be eREG (k, l ). In this case, k is ≤K and 1≤ k (in the sub-frame K is the number of PRB pairs), l is a 1≤ l ≤12 in the case of a normal CP in the case of 1≤ l ≤14, extended CP.

When using an eREG defined based on an OFDM symbol, permutation is performed on each eRB for one OFDM symbol. Thus, for a fixed value of l , permutation is performed while changing the value of k .

(2) About Specifically, l = 1, k by calculating a '= (k + P _l) mod K (P _l is randomization / permutation factor) of k', eREG (k, l ) eREG ( k ', l ).

(3) When k 'is calculated, the value of k is increased by 1 ( k = k + 1).

(4) Repeat (2) and (3) until k = K.

(5) While increasing the value of l ( l = l + 1), repeat (2) to (4) until l = 14 for normal CP and l = 12 for extended CP do.

Note that the value of l does not change during randomization (permutation). That is, eREG randomization is performed in the same OFDM symbol.

FIG. 7 is a diagram schematically illustrating distribution of resources to which ePDCCH is mapped using eREG according to the present invention. In FIG. 7, PCFICH, PHICH, PDCCH, and the like are mapped to the control region 700, and PDSCH and ePDCCH are mapped to the data region 710. Referring to FIG. 7, finally, the ePDCCH is distributedly mapped over eRBs 720-1, ..., 720-K in each same OFDM symbol. In FIG. 7, the number of ODEM symbols, i.e., the number of eREGs in the PRB pair, becomes 14 for a normal CP and 12 for an extended CP.

According to the randomization factor (P _l), it can be determined a dispersion pattern. For example, the ePDCCH may be mapped to the i th eRB in the x th OFDM symbol, and may be located in the i + j th eRB in the y th OFDM symbol (x, y, i, j are integers, and x, y ≦ in a normal CP). 14, x, y ≦ 12 in the extended CP, i + j ≦ K). The difference in the location mapped in each OFDM symbol may be a result of permutation according to the value of P _l .

8 is a diagram schematically illustrating an example in which ePDCCH is distributed mapped based on an eREG according to the present invention. In the example of Figure 8, to set the value of P _l to l, and applying a cyclic shift to, k '= ePDCCH shows a distributed mapping of the result is set to (k + l). When two ePDCCHs of ePDCCH1 and ePDCCH2 are distributedly mapped to eRBs 810-1,..., 810 -K, each ePDCCH may be mapped while moving by one OFDM symbol for each eRB.

EREG defined based on subcarrier

EREG defined based on subcarriers: One eREG includes all REs belonging to the same subcarrier within an eRB. Here, RE means an RE that is not mapped to CRS and DMRS, and ePDCCH is mapped to these REs.

9 schematically illustrates eREGs defined based on a subcarrier according to the present invention. As shown, in the subframe, the CRS and the DMRS are located according to each pattern. Subbands may include a CRS, may include a DMRS, or may not include both a CRS and a DMRS. Accordingly, different eREGs may include different numbers of REs. Herein, the RE included in the eREG, as described above, refers to an RE that is not mapped to the CRS and the DMRS and that can be used for transmission of the ePDCCH.

Even when using an eREG, the ePDCCH may be distributed and mapped to a transmission resource. In this case, the ePDCCH may be mapped for each eREG.

In this case, distributed mapping of the ePDCCH may be performed through an interleaver, or may be performed through randomization that simply permutates the eREG. For convenience of description, unless otherwise stated, 'interleaving' herein includes randomization.

In this embodiment, distributed mapping of ePDCCH by permutation will be described as an example of interleaving for distributed transmission of ePDCCH.

The distributed mapping method of ePDCCH by permutation is as follows:

(1) Permutation is performed between eRBs for each subcarrier.

Let eREG corresponding to k th eRB and l th subcarriers in a subframe be eREG (k, l ). Where k is 1 ≦ k ≦ K (K in the subframe is the number of PRB pairs) and l is 1 ≦ l ≦ 12.

When using an eREG defined based on a subcarrier, permutation is performed for each eRB to determine an eREG in which the corresponding ePDCCH is located in the eRB. Thus, l is determined for a fixed k value.

(2) About Specifically, k = 1, l to calculate a _{'= (l + P k)} mod 12 of l (P _k is randomization / permutation factor)', eREG (k, l ) eREG ( k , l ').

(3) When l 'is calculated, increase the value of l by 1 ( l = l +1).

(4) Repeat (2) and (3) until l = 12.

(5) While increasing the value of k ( k = k + 1), repeat (2) to (4) until k = 12.

Note that in the randomization / permutation process, the k value does not change. That is, eREG randomization is performed within the same eRB.

FIG. 10 is a diagram schematically illustrating distribution mapping of an ePDCCH using an eREG according to the present invention. In FIG. 10, PCFICH, PHICH, PDCCH, and the like may be mapped to the control region 1000, and PDSCH and ePDCCH may be mapped to the data region 1010. ERBs are defined in subcarrier units.

In FIG. 10, the distribution pattern of the ePDCCH may be determined according to the randomization factor P _k . For example, in one subframe, the ePDCCH that was located in the x-th eREG (subcarrier) in the i-th eRB may be located in the y-th eREG in the K-th OFDM symbol according to P _k (x, y, i are integers, x, y ≤ 12, i ≤ K).

EREG without CRS

In the case of an extension carrier or a multimedia broadcast single frequency network (MBSFN), PDCCH and CRS do not exist. In this case, therefore, it is possible to define an eREG that is fully DMRS based.

FIG. 11 schematically illustrates a subframe structure for a case in which a PDCCH and a CRS do not exist, such as an extended carrier or MBSFN.

Referring to FIG. 11, an OFDM symbol may include 6 REs and some OFDM symbols may include 12 REs according to the DMRS pattern.

Accordingly, when there is no CSR as shown in the example of FIG. 11, when defining an eREG based on an OFDM symbol, the number of REs included in the eREG may be specified. For example, (1) eREG may be defined to include three REs, and (2) eREG may be included to include six REs. Also, (3) As in the case where the eREG is defined based on the OFDM symbol, the eREG may be defined to include all REs belonging to one OFDM symbol.

In the case of defining an eREG to include three REs as in definition (1), four eREGs exist in an ODFM symbol without DMRS in FIG. 11, and two eREGs exist in an OFDM symbol in which DMRS exists. do.

In the case of defining an eREG to include six REs as in definition (2), two eREGs exist in an OFDM symbol in which a DMRS does not exist in FIG. 11, and one eREG exists in a symbol in which a DMRS exists. .

As in definition (3), in case of defining REG for each OFDM symbol, there are 14 eREGs in FIG. FIG. 11 illustrates a normal CP, and in case of an extended CP, 12 eREGs exist.

The defined eREG may be randomized among eRBs in the same OFDM symbol after the ePDCCH is mapped as described above. For example, as in definition (1) or definition (2), when there may be two or more eREGs belonging to an OFDM symbol in an eRB, the method described in randomization of an eREG defined based on subcarriers may be applied. In addition, when there is one eREG belonging to OFDM in one eRB as defined (3), the randomization method described in the randomization of eREG defined based on an OFDM symbol can be applied.

OCC for distributed transmission

In distributed transmission of the ePDCCH, several ePDCCHs may be made to share the same PRB pair. For example, a code division multiplexing (CDM) scheme may be applied using an orthogonal cover code (OCC). OCC means a code that can be applied to a sequence having orthogonality with each other. Generally, different sequences may be used to distinguish a plurality of channels, but a plurality of channels may be distinguished using an OCC. Therefore, OCC can be used to increase the multiplexing capacity.

If the length of the OCC is 2, two ePDCCHs share the same PRB pair, so that two terminals can receive the ePDCCH through the same PRB pair. When the length of the OCC is n, n ePDCCHs share the same PRB pair, and n terminals may receive the ePDCCH through the same PRB pair.

12 schematically illustrates an eREG defined when using an OCC of length 2 in accordance with the present invention. Referring to Figure 12, eREG based CDM method is described as follows:

(1) CDM in the frequency domain between different subcarriers in a PRB pair

This scheme may be matched to the subcarrier based eREG. Since 12 subcarriers exist in each PRB, spreading factors may be 2, 4, 6, and 12.

In consideration of the symmetry of the PRB pairs, an OCC of length 2 may be used. That is, as shown, the first part of the OCC may be allocated to the PRB of the upper half, and the second part of the OCC may be allocated to the PRB of the lower half. Therefore, 1 is assigned to the first part of the OCC for the first user terminal and 1 is assigned to the second part as a code ([1, 1]), and 1 is assigned to the first part of the OCC for the second user terminal. In the second part, -1 may be given as a code ([1, -1]) so that two user terminals use the same PRB.

If other spreading factors (length of OCC) 4, 6, 12 are applied, some REs may be muted.

(2) CDM in time domain between different OFDM symbols in a PRB pair

If the extended carrier is applied and there is no PDCCH region, unlike in FIG. 12, the first part of the length 2 OCC is allocated to the front PRB (the first slot of the subframe) of the subframe, and the two parts of the length 2 OCC are different. The second part may be allocated to the rear PRB (the rear slot of the subframe) of the subframe.

Therefore, even in this case, two user terminals may receive the ePDCCH through the same PRB. Even in this case, if the DMRS antenna port is 2, it may be assumed that 4 DMRS antenna ports which mute some REs when mapping the ePDCCH.

13 is a flowchart schematically illustrating an operation of a terminal for obtaining control information from an ePDCCH in a system according to the present invention.

Referring to FIG. 13, upon receiving a signal through a physical channel, the terminal performs de-interleaving in the ePDCCH region (S1310). In the present specification, as described above, unless otherwise specified, interleaving includes randomization. Also, unless otherwise specified herein, deinterleaving includes de-randomization. The terminal may combine the interleaved or distributed ePDCCH through deinterleaving.

The assumption of deinterleaving performed by the terminal is performed in the reverse order of the above-described interleaving process. Information on interleaving, for example, information on an interleaving matrix, information on a permutation factor, and the like may be transmitted to the terminal in advance.

When the PRB pair (eRB) to which the ePDCCH is mapped is divided into N subblocks and interleaved, the UE performs de-interleaving accordingly. In addition, even when the eRB to which the ePDCCH is mapped is interleaved based on the eREG, the UE may perform de-interleaving corresponding to the performed interleaving method.

The terminal demodulates the symbols (S1320).

Subsequently, the terminal decodes the demodulated symbol (S1330).

The UE blindly detects the ePDCCH based on the search space with respect to the decoded symbol (S1340). Blind detection is also referred to as blind decoding. The blind detection is a method of demasking a desired identifier in a CRC of a received physical control channel and checking a CRC error to determine whether the corresponding physical control channel is its own physical control channel. Here, the physical control channel may include an ePDCCH.

Since a plurality of physical control channels may be transmitted in one subframe, the terminal monitors the plurality of physical control channels every subframe. Here, the monitoring means that the terminal attempts to decode the physical control channel according to the format of the target physical control channel.

To reduce the burden of blind searching, a search space can be used. The search space is divided into a common search space and a UE-specific search space. The common search space is a space for searching for a physical control channel having common control information. The common search space includes 16 CCEs up to CCE indexes 0 to 15 and may support a physical control channel having a CCE aggregation level of {4, 8}. The UE-specific search space may support a physical control channel having a CCE aggregation level of {1, 2, 4, 8}.

14 is a flowchart schematically illustrating an operation of a base station for distributed transmission of an ePDCCH in a system to which the present invention is applied.

Referring to FIG. 14, the base station encodes a symbol to be transmitted (S1410). As described in FIG. 1, when transmitting control information, the base station performs encoding after adding a CRC to the control information and performing scrambling. The base station may encode control information to be transmitted on the ePDCCH.

The base station modulates the encoded symbol (S1420). The base station may map control information to transmission resources of the data region allocated to the ePDCCH.

Subsequently, the base station interleaves the transmission resources mapped to the ePDCCH (S1430). At this time, the base station may interleave the PRB pair (eRB) in which the ePDCCH is transmitted into N blocks, or define an eREG to perform interleaving based on the eREG.

The method of interleaving performed by the base station is as described above.

The base station may distribute transmission of the interleaved resource ePDCCH (S1440).

15 is a block diagram schematically illustrating a configuration of a base station in a system to which the present invention is applied. Referring to FIG. 15, the base station 1500 includes a control unit 1510, a memory 1520, and an RF unit 1530.

The base station transmits and receives necessary data through the RF unit 1530. The RF unit 1530 may include a plurality of antennas to support multi-antenna transmission (MIMO: Multi-Input Multi-Output).

The memory 1520 may store information necessary for the operation of the base station. For example, the memory 1520 may store information on resources allocated to the ePDCCH, information on interleaving, and the like.

The controller 1510 implements the functions, processes, and / or methods proposed herein. The controller 1510 may set control information and map it to resources. The control information set by the controller 1510 includes information transmitted on the ePDCCH. The controller 1510 may encode and modulate control information transmitted through the ePDCCH, map it to a resource allocated to the ePDCCH, and interleave it so that the ePDCCH is distributed and transmitted.

The controller 1510 may include a distribution mapping unit 1540 and a control information setting unit 1550. The control information setting unit 1550 may set information to be transmitted on the PDCCH, ePDCCH, or the like. The set information may be transmitted on the control channel according to the Downlink Control Informaton (DCI) format.

The distributed mapping unit 1540 may encode and modulate control information, map it to a transmission resource, and interleave it. Among these, a specific method related to interleaving of the ePDCCH is as described above.

16 is a block diagram schematically illustrating a configuration of a terminal in a system to which the present invention is applied. Referring to FIG. 16, the terminal 1600 includes a controller 1610, an RF unit 1620, and a memory 1630.

The terminal may transmit and receive necessary information through the RF unit 1620. The RF unit 1620 may include a plurality of antennas and may support MIMO based thereon.

The memory 1630 may store information necessary for the terminal to perform communication. For example, the memory 1630 may receive and store information regarding interleaving of the ePDCCH in advance.

The controller 1610 implements the functions, processes, and / or methods proposed herein. The controller 1620 may de-interleave the received data, demodulate it, and perform decoding. When performing de-interleaving, the controller 1620 may perform de-interleaving vice versa, corresponding to the interleaving method performed by the base station. The controller 1620 may blindly detect the ePDCCH with respect to the decoded symbol to obtain control information transmitted on the ePDCCH.

The controller 1610 may include a channel detector 1640 and a control information processor 1650. The channel detector 1640 may detect the ePDCCH by performing blind detection, and the control information processor 1650 processes the information transmitted on the detected ePDCCH.

In the above-described exemplary system, the methods are described on the basis of a flowchart as a series of steps or blocks, but the present invention is not limited to the order of the steps, and some steps may occur in different orders or simultaneously . It will also be understood by those skilled in the art that the steps shown in the flowchart are not exclusive and that other steps may be included or that one or more steps in the flowchart may be deleted without affecting the scope of the invention.

The above-described embodiments include examples of various aspects. While it is not possible to describe every possible combination for expressing various aspects, one of ordinary skill in the art will recognize that other combinations are possible. Accordingly, it is intended that the invention include all alternatives, modifications and variations that fall within the scope of the following claims.

Claims (18)

De-interleaving the received Enhanced Downlink Control Channel (ePDCCH) region;
Demodulating the deinterleaved modulation symbol; And
Performing decoding the demodulated symbol,
In the deinterleaving step,
deinterleaving the subblocks mapped to the ePDCCH;
And the subblock is divided into a predetermined number of resource blocks allocated to the ePDCCH. The method of claim 1, wherein the deinterleaving is
The control information receiving method, characterized in that performed between a plurality of resource blocks allocated to the ePDCCH region. The method of claim 1, wherein the number of subblocks per resource block is the same as the number of resource blocks allocated to the ePDCCH transmission. 4. The method of claim 3, wherein the deinterleaved subblocks are received in different resource blocks. 5. The method of claim 1, wherein the sub block is
The resource block allocated to the ePDCCH is divided into orthogonal frequency division multiplexing (OFDM) symbol units.
And a resource element that does not transmit a reference signal among the resource elements belonging to the OFDM symbol. The method of claim 5, wherein in the deinterleaving step,
Deinterleaving is performed on subblocks mapped to the same ePDCCH among subblocks belonging to different resource blocks.
The subblocks mapped to the same ePDCCH belong to different OFDM symbols according to resource blocks. The method of claim 1, wherein the sub block is
As the resource block allocated to the ePDCCH is divided into subcarriers,
And a resource element that does not transmit a reference signal among the resource elements belonging to the subcarrier. The method of claim 7, wherein in the deinterleaving step,
Deinterleaving is performed on subblocks mapped to the same ePDCCH among subblocks belonging to different resource blocks.
The subblocks mapped to the same ePDCCH belong to different subcarriers according to resource blocks. Mapping an ePDCCH to be transmitted to a resource block; And
Performing interleaving on the resource block to which the ePDCCH is mapped;
In the interleaving step
And interleaving the resource block to which the ePDCCH is mapped into subblocks. The method of claim 9, wherein the interleaving,
The control information transmission method, characterized in that performed between a plurality of resource blocks allocated to the ePDCCH region. 10. The method of claim 9, wherein the number of subblocks per resource block is the same as the number of resource blocks allocated to the ePDCCH transmission. 12. The method of claim 11, wherein the subblocks are distributed and transmitted to different resource blocks by the interleaving. The method of claim 9, wherein the sub block is
The resource block allocated to the ePDCCH is divided into orthogonal frequency division multiplexing (OFDM) symbol units.
And a resource element which does not transmit a reference signal among the resource elements belonging to the OFDM symbol. The method of claim 13, wherein in the interleaving step,
Interleaving to distribute subblocks mapped to the same ePDCCH to different resource blocks;
The subblocks mapped to the same ePDCCH belong to different OFDM symbols by the interleaving. The method of claim 9, wherein the sub block is
As the resource block allocated to the ePDCCH is divided into subcarriers,
And a resource element which does not transmit a reference signal among the resource elements belonging to the subcarrier. The method of claim 15, wherein in the interleaving step,
Interleaving to distribute subblocks mapped to the same ePDCCH to different resource blocks;
The subblocks mapped to the same ePDCCH belong to different subcarriers by the interleaving. RF unit for receiving the ePDCCH; And
It includes a control unit for obtaining necessary information from the received ePDCCH,
The control unit,
and dividing the resource blocks mapped to the ePDCCH to de-interleaving the distributed received subblocks to generate a modulation symbol. RF unit for transmitting the ePDCCH; And
A control unit for interleaving the resource block to which the ePDCCH to be transmitted is mapped;
The control unit,
And interleaving the resource block to which the ePDCCH is mapped into subblocks.

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