KR20130126438A - Method and base station for multiplexing control information in data region - Google Patents

Abstract

The present invention relates to a technique for multiplexing and transmitting control information in a data area in a wireless communication system. The present invention provides a method of allocating control information of at least two terminals to resource elements of at least two subcarriers adjacent to or not adjacent to a data area of at least one of two slots of a subframe and time-control information. A method of multiplexing control information in a data area including transmitting to a terminal through a frequency resource.

Description

METHOD AND BASE STATION FOR MULTIPLEXING CONTROL INFORMATION IN DATA REGION}

The present invention relates to a technique for multiplexing and transmitting control information in a data area in a wireless communication system.

As communications systems evolved, consumers, such as businesses and individuals, used a wide variety of wireless terminals. In a mobile communication system such as the current 3GPP family Long Term Evolution (LTE) and LTE-A (LTE Advanced), a high-speed and large-capacity communication system capable of transmitting and receiving various data such as video and wireless data, , It is required to develop a technology capable of transmitting large-capacity data based on a wired communication network. As a method for transmitting a large amount of data, a method of efficiently transmitting data through a plurality of element carriers can be used.

In this system, the time-frequency resource is divided into a region for transmitting a control channel (for example, a physical downlink control channel (PDCCH)) and a region for transmitting a data channel (for example, a Physical Downlink Shared CHannel (PDSCH) .

In order to improve the performance of a wireless communication system, technologies such as multiple-input multiple-output (MIMO) and coordinated multi-point transmission / reception (CoMP) have been considered. More control information may be required to use this technique. However, the limited control area may be insufficient to cover all control channels.

An object of the present invention is to provide an apparatus and method for efficiently transmitting control information to a terminal in a wireless communication system.

In order to achieve the above object, in one aspect, the present invention provides at least two subcarriers (adjacent or not adjacent to a data area of at least one slot of two slots of a Physical Resource Block pair). Allocating control information of at least two terminals to resource elements of subcarriers and transmitting the control information to the terminals through time-frequency resources. Provide a way to.

In another aspect, the present invention provides a control channel element comprising at least two groups of resource elements having the same index with respect to resource elements indexed by repeating 16 numbers in a resource block pair (Physical Resource Block pair) with frequency priority. allocating control information of at least two terminals to enhanced control channel elements (eCCEs) and transmitting the control information to the terminals through a time-frequency resource. To provide.

In another aspect, the present invention provides a resource element of at least two subcarriers adjacent to or not adjacent to a data area of at least one of two slots of a physical resource block pair. Elements) and a base station for multiplexing control information in a data area including a resource allocation unit for allocating control information of at least two terminals and a transmitter for transmitting the control information to the terminals through time-frequency resources. .

In another aspect, the present invention provides a control channel element composed of at least two groups of resource elements having the same index for resource elements indexed by repeating 16 numbers in frequency-first order in a physical resource block pair. The control information is allocated to a data area including a resource allocation unit for allocating control information of at least two terminals to enhanced control channel elements (eCCEs) and a transmitter for transmitting the control information to the terminals through time-frequency resources. Provides a base station to multiplex.

According to the present invention described above, in a wireless communication system, a base station can efficiently transmit control information to a terminal.

1 illustrates an example of a structure of a downlink resource in a Long Term Evolution (LTE) or LTE-Advanced (LTE-A) system, and illustrates one resource block pair in the case of normal CP.
2 to 5 show examples of resource allocation according to an embodiment for a pair of resource blocks including a data area and a control area.
6 to 13 illustrate examples of resource allocation according to an embodiment of a resource block pair of an NCT in which a control region does not exist and only a data region exists.
14 is an internal block diagram of a base station according to an embodiment of the present invention.
15 is a flowchart illustrating a method of multiplexing control information into a data area according to an embodiment of the present invention.
16 to 17 illustrate examples of assigning indexes to resource elements in a resource block pair.
18 to 19 illustrate examples of determining the same index as one resource element group for resource elements assigned an index in a resource block pair.
20 to 21 show examples of resource allocation according to an embodiment for a resource block pair divided into resource element groups.
22 is an internal block diagram of a base station according to another embodiment of the present invention.
23 is a flowchart illustrating a method of multiplexing control information into a data area 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. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible 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.

In addition, in describing the component of this invention, terms, such as 1st, 2nd, A, B, (a), (b), can be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected to or connected to the other component, It should be understood that an element may be "connected," "coupled," or "connected."

In wireless communication, one radio frame (radioframe) consists of 10 subframes, and one subframe consists 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 seven (or normal cyclic prefix (normal CP)) or six (or extended cyclic prefix (or extended CP)) orthogonal frequency division modulation (OFDM) symbols in the time domain.

In the wireless communication, the frequency domain may be configured by, for example, a subcarrier unit of 15 kHz interval.

In downlink, time-frequency resources may be configured 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. One subcarrier (two slots) on the time axis A resource consisting of 12 subcarriers on the frequency axis may be referred to as a resource block pair (RBP). The total number of resource blocks varies according to 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 include 14x12 resource elements (normal CP) or 12X12 resource elements (extended CP).

1 illustrates an example of a structure of a downlink resource in a Long Term Evolution (LTE) or LTE-Advanced (LTE-A) system, and illustrates one resource block pair in the case of a normal cyclic prefix (CP).

Referring to FIG. 1, in the case of normal CP, one resource block pair includes 14 OFDM symbols (l = 0 to 13) and 12 subcarriers (k = 0 to 11). In the example of FIG. 1, a region (l = 0 to 2) consisting of three OFDM symbols in front of fourteen OFDM symbols belonging to one resource block pair includes a physical control format information channel (PCFICH) and a physical hybrid ARQ indicator (PHICH). A control region 110 allocated for a control channel such as CHannel), a physical downlink control channel (PDCCH), etc., and the remaining regions (l = 3 to 13) are allocated for a data channel such as a physical downlink shared channel (PDSCH). It may be a data area 120. Although three OFDM symbols are shown in FIG. 1 for the control region 110, it is possible to assign one to four OFDM symbols for the control region 110. The size information of the OFDM symbol of the control region 110 may be transmitted through the PCFICH.

The PDCCH may be transmitted over the entire system band, and the PDSCH may be transmitted on a resource block basis. The user terminal may first check the PDCCH set for the user, and if there is no data corresponding to the user, take a micro sleep mode to reduce power consumption of the user terminal in the data area 120.

Referring to FIG. 1, a reference signal may be mapped to a specific resource element of downlink. That is, the common reference signal or cell-specific reference signal (CRS) 130, the demodulation reference signal or the UE-specific reference signal (DeModulation Reference Signal or UE-specific Reference Signal) in the downlink The DM-RSs 132 and 134 and the Channel Status Information Reference Signal (CSI-RS) may be transmitted. In FIG. 1, only the CRS 130 and the DM-RSs 132 and 134 are shown for convenience of description.

The CRS 130 in the control region 110 may be used for channel estimation for decoding the PDCCH, and the CRS 130 in the data region 120 may be used for downlink channel measurement. Channel estimation for data decoding of the data region 120 may be performed using the DM-RSs 132 and 134. The DM-RSs 132 and 134 are multiplexed with reference signals for a plurality of layers using orthogonal codes. For example, in the case of four layer transmission, an orthogonal code having a length of 2 may be applied to two reference signal resource elements consecutive in the time axis, and two different reference signals may be multiplexed for each reference signal group. In the case of layer transmission, four orthogonal signals having a length of 4 may be applied to four reference signal resource elements distributed in the time axis, thereby multiplexing four different reference signals for each reference signal group.

In case of one or two layer transmission, since only one DM-RS group 1 132 can transmit the reference signal of each layer, the other DM-RS group 2 134 can be used as data transmission. have. DM-RS corresponding to each layer is transmitted by applying the same precoding applied to the layer. This enables decoding of data at the receiving end (terminal) without the information of precoding applied at the transmitting end (base station).

In a wireless communication system, a control channel is required to efficiently use limited resources. However, the resources of the control area 110 reduce the resources of the data area 120 used for data transmission as overhead of the system. In an OFDM-based LTE system, one resource block pair is composed of 14 or 12 OFDM symbols, of which up to three OFDM symbols are used for the control region 110 and the remaining OFDM symbols are used for the data region 120. I use it. Meanwhile, in the LTE-A system capable of transmitting data to more users, the increase in system capacity may be limited due to the resources of the conventional limited control region 110. Therefore, an increase in control channel resources is inevitable, and thus a control channel transmission / reception method for multiple users using a spatial division multiplexing technique in the data region 120 may be considered. This method is to transmit and receive the control channel in the data area 120. For example, the control channel transmitted in the data region 120 may be called an extended PDCCH (E-PDCCH) or an enhanced PDCCH, but is not limited thereto.

In the data region 120, the control channel resource may be allocated in units of resource blocks (or resource block pairs) for compatibility with data channel (eg, PDSCH) resources. Since the decoding reference signal (DM-RS) may be used when transmitting the control channel in the data region 120, the control channel may be transmitted using a beam forming technique. Therefore, the reception reliability of the control channel may be improved according to the array gain obtained from the beamforming transmission.

In an embodiment, the resource block for transmitting the control channel in the data region 120 may be set based on a resource block group composed of consecutive resource blocks in the frequency domain.

The embodiments provide a method and apparatus for allocating control information to resource elements of a data region when extending a control channel in the data region in a 3GPP LTE-Advanced system. Specifically, in the 3GPP LTE / LTE-Advanced, a new carrier type (hereinafter referred to as 'NCT'), CoMP (Coordinated Multipoint Transmission / Reception), in Carrier Aggregation (CA), Extended (enhanced) PDCCH (ePDCCH) for downlink multi-input multi-output (MIMO) may be allocated to PDSCH (Physical Downlink Shared Channel) which is a data region.

In this specification, allocation of control information is used in the same sense as allocation of a control channel. In other words, the allocation of control channels in this specification means allocating control information to resource elements.

In this case, the control channel is allocated in two slots, that is, a unit of a Physical Resource Block (PRB) pair corresponding to a subframe, and a PDSCH and an ePDCCH cannot be simultaneously assigned to one PRB pair. In other words, PDSCH and ePDCCH can not be multiplexed in one PRB pair.

Meanwhile, control information or control channels of two or more UEs may be allocated to two or more PRB pairs or may be allocated in one PRB pair to multiplex control information of UEs.

When multiplexing control information of UEs, the control information may be allocated to two or more PRB pairs in a localized or distributed manner or may be allocated in one PRB pair in a localized and distributed manner.

Multiplexed control information of terminals can support both localized transmission and distributed transmission. Localized transmission improves performance at low speed and distributed transmission The performance is improved compared to the existing PDCCH which transmits control information to the control region at high speed.

Meanwhile, it may support a common search space (CSS) in connection with a search space. At this time, common Radio Network Temporary Identities (RNTI) can be transmitted, including System Information RNTI (SI-RNTI), Paging RNTI (P-RNTI), Random Access RNTI (RA-RNTI), and Transmit Power Control (TPC) -PUCCH. (Physical Uplink Control Channel) -RNTI and TPC-PUSCH (Physical Uplink Shared Channel) -RNTI may be used.

Considering the frequency-domain inter-cell interference coordination (ICIC) for CSS, the increased performance of CSS (CoMP scn 4), and the new type of carrier (NCT), the first proposal may not add CSS to the ePDCCH or the second. In addition, CSS may be added to the ePDCCH, and as a third option, CSS may be added to the PDCCH and the ePDCCH simultaneously.

The following points can be reflected in the design of ePDCCH.

FIG. 2 is a diagram for allocating control information (ePDCCH) of three UEs (UE) to a data region in a resource block pair based on frequency-division multiplexing (FDM). Spatial frequency block coding (SFBC) can be applied to each adjacent subcarrier, thereby improving performance.

Since only at least one of the PCFICH and the PHICH is allocated to the control region in the RB pair, and control information corresponding to the PDCCH is allocated to the data region through the ePDCCH, the control region may be allocated only two or less OFDM symbols.

Referring to FIG. 2, control information for each terminal is allocated to resource elements corresponding to four adjacent subcarriers and third to fourteenth symbols in data regions of two slots of a resource block pair. The number of resource elements (RE) allocated to each terminal is 48, which is larger than 36RE, which is a unit of a conventional control-channel element (CCE). This is because UE-specific reference signals (UE-specific RS) and channel estimation reference signals (CSI-RS) are allocated to each region.

Control information for each terminal may be allocated except for a resource element to which a reference signal is assigned. For example, referring back to FIG. 1, the base station may be assigned a resource element 132 to which a DeModulation Reference Signal (DM-RS) signal is allocated. Alternatively, except for 134, control information of each terminal may be allocated. When the control information is allocated except for the resource element to which a specific reference signal is allocated, as shown in FIG. 2, even if there are 48 resource elements to allocate control information for each terminal, the control can be transmitted through the allocated resource element. The amount of information will be less than 48 RE.

If the decoding unit for ePDCCH is extended from Quadrature Phase Shift Keying (QPSK) to 16QAM (Quadrature Amplitude Modulation), or if rank-2 Multiple Input Multiple Output (MIMO) is used, the number of REs can be reduced, but the stability of control channel characteristics will be inferior. Can be.

FIG. 3 is an embodiment of allocating control information (ePDCCH) for three UEs to a data region in a resource block pair in a frequency division based distributed manner.

Referring to FIG. 3, at least one of the PCFICH and the PHICH is allocated within two OFDM symbols, and the control information for each UE is provided in each of four non-adjacent subs in the data region of two slots of a resource block pair. It is assigned to the carrier and the resource element corresponding to the third to fourteenth symbols.

FIG. 4 illustrates an embodiment of allocating control information (ePDCCH) for six UEs to a data region in a resource block pair in a centralized manner based on frequency division (FDM) and time division (TDM).

Referring to FIG. 4, control information (ePDCCH) for UE 1 to UE 3 is allocated to resource elements of four adjacent subcarriers in a data region of slot 1 of two slots of a resource block pair. Control information (ePDCCH) for UE 6 is allocated to resource elements of four adjacent subcarriers in the data area of slot 2 of two slots of the resource block pair.

Referring to FIG. 4, since the control area is included in slot 1, the number of resource elements corresponding to the data area is smaller than that of slot 2. However, slot 1 is characterized by being ahead of slot 2 in the time domain.

According to such a feature, the ePDCCH allocated to slot 1 may enable early decoding by allocating an ePDCCH to a terminal using a large PDSCH (a terminal using a larger capacity of data through the PDSCH). In addition, the ePDCCH allocated to the slot 2 may be control information for the terminal to which the low capacity PDSCH is allocated. In other words, when the base station allocates control information of two terminals by time division in a slot unit in the data area, the base station performs time control information on a terminal using a larger capacity of data through the PDSCH among the control information of the two terminals. It can be assigned to the slot that is advanced on the area.

The ePDCCH allocated to slot 2 may further include an uplink control signal (UL grant) because there are more resource elements allocated than the ePDCCH allocated to slot 1.

FIG. 5 is an embodiment of allocating control information (ePDCCH) for six UEs to a data division in a resource block pair in a frequency division (FDM) and time division (TDM) based distributed type.

Referring to FIG. 5, control information (ePDCCH) for UE 1 to UE 3 is allocated to resource elements of four non-adjacent subcarriers in a data region of slot 1 of two slots of a resource block pair, and the UE Control information (ePDCCH) for 4 to UE 6 is allocated to resource elements of four non-adjacent subcarriers in a data region of slot 2 of two slots of a resource block pair.

FIG. 6 illustrates an embodiment in which control information (ePDCCH) for three UEs is allocated to a data division based on frequency division in a NCT resource block pair in which a control region does not exist and only a data region exists.

Referring to FIG. 6, a control region is not allocated to a resource block pair, only a data region is allocated, and control information for each terminal is provided by four adjacent subcarriers in the data region (total region) of two slots of the resource block pair. Assigned to resource elements corresponding to There are 56 resource elements allocated to each terminal.

FIG. 7 illustrates an embodiment in which control information (ePDCCH) for three UEs is allocated to a data division based on frequency division in a NCT resource block pair in which a control region does not exist and only a data region exists.

Referring to FIG. 7, control information for each terminal is allocated to resource elements corresponding to four non-adjacent subcarriers in two data slots of a resource block pair.

FIG. 8 illustrates an embodiment in which control information (ePDCCH) for six terminals is allocated to a data division based on frequency division and time division in a NCT resource block pair in which no control region exists but only a data region. Yes.

Referring to FIG. 8, control information (ePDCCH) for UE 1 to UE 3 is allocated to resource elements of four adjacent subcarriers in a data region of slot 1 of two slots of a resource block pair, and is allocated to UE 4 to UE. Control information (ePDCCH) for UE 6 is allocated to resource elements of four adjacent subcarriers in the data area of slot 2 of two slots of the resource block pair. There are 28 resource elements allocated to each terminal.

FIG. 9 is a diagram illustrating an embodiment of allocating control information (ePDCCH) for six terminals to a frequency division and a time division based distributed type in a data region in a NCT resource block pair in which a control region does not exist and only a data region exists. Yes.

Referring to FIG. 9, control information (ePDCCH) for UE 1 to UE 3 is allocated to resource elements of four subcarriers that are not adjacent in a data region of slot 1 of two slots of a resource block pair. Control information (ePDCCH) for 4 to UE 6 is allocated to resource elements of four non-adjacent subcarriers in a data region of slot 2 of two slots of a resource block pair.

According to an embodiment of the present disclosure, the number of terminals that can be multiplexed in one resource block pair may be 2 to 8. An example in which the number of terminals is three or six has been described above, and an example in which the number of terminals is four or eight will be described later.

FIG. 10 illustrates an embodiment in which control information (ePDCCH) for four terminals is allocated to the data region in a frequency division-based centralized manner in a NCT resource block pair in which a control region does not exist and only a data region exists.

Referring to FIG. 10, a control region is not allocated to a resource block pair, only a data region is allocated, and control information for each terminal is allocated to three adjacent subcarriers in the data region (total region) of two slots of the resource block pair. Assigned to resource elements corresponding to

FIG. 11 is a diagram for allocating control information (ePDCCH) for four UEs to a data area in a frequency-based distributed form in a NCT resource block pair in which a control area does not exist and only a data area exists.

Referring to FIG. 11, control information for each terminal is allocated to resource elements corresponding to four non-contiguous subcarriers in two data slots of a resource block pair.

Since the NCT can remove the PDCCH in the existing carrier type, the number of resource elements for allocating control information for each terminal can be increased to 56 in the case of three terminal assignments as shown in the embodiments of FIGS. 6 to 7. . On the other hand, when allocating four terminals in units of three subcarriers as shown in FIGS. 10 to 11, 42 resource elements may be allocated to each terminal, thereby more efficiently utilizing radio resources.

12 is a diagram illustrating an embodiment of allocating control information (ePDCCH) for eight terminals to a frequency division and time division based centralized type in a data region in a NCT resource block pair in which a control region does not exist and only a data region exists. Yes.

Referring to FIG. 12, control information (ePDCCH) for UE 1 to UE 4 is allocated to resource elements of three adjacent subcarriers in a data region of slot 1 of two slots of a resource block pair, and is represented by UE 5 to UE. Control information (ePDCCH) for 8 is allocated to resource elements of three adjacent subcarriers in the data area of slot 2 of the two slots of the resource block pair. There are 21 resource elements allocated to each terminal.

FIG. 13 is a diagram illustrating an embodiment of allocating control information (ePDCCH) for eight terminals to a frequency division and time division based distributed type in a data region in a NCT (New Carrier Type) resource block pair in which a control region does not exist and only a data region exists. Yes.

Referring to FIG. 13, control information (ePDCCH) for UE 1 to UE 4 is allocated to resource elements of three non-adjacent subcarriers in a data region of slot 1 of two slots of a resource block pair. Control information (ePDCCH) for 5 to UE 8 is allocated to resource elements of three non-adjacent subcarriers in a data region of slot 2 of two slots of a resource block pair.

Although not shown in the drawing, when the number of terminals is five, in the case where the number of terminals described with reference to FIGS. 8 to 9 is six, the control information is not allocated to an area for allocating control information of any one terminal. When the number of terminals is seven, the embodiment of the specification may be applied. In the case where the number of terminals described with reference to FIGS. 12 to 13 is eight, control information is not allocated to an area for allocating control information of any one terminal. In other ways, embodiments of the present disclosure may be applied.

14 is an internal block diagram of a base station according to an embodiment of the present invention.

Referring to FIG. 14, the base station 1400 provides control information of at least two terminals to resource elements of at least two subcarriers adjacent to or not adjacent to a data area of at least one of two slots of a resource block pair. The resource allocator 1410 may be allocated, and the transmitter 1420 may transmit the control information to the terminals through time-frequency resources.

As described with reference to FIGS. 2 to 13, the resource allocator 1410 may allocate control information by frequency division or frequency and time division, and excludes resource elements to which a DM-RS (DeModulation Reference Signal) signal is allocated. And control information may be allocated. In addition, the resource allocator 1410 allocates control information of two terminals by time-division by slot unit in the data area, and controls a terminal using a larger capacity of data through PDSCH among control information of the two terminals. Information can also be assigned to slots earlier in the time domain. The RB pair may form a control region in a symbol within the second, and the RB pair may exist only in the data region without the control region. The number of terminals allocated by the resource allocator 1410 may be two to eight.

15 is a flowchart illustrating a method of multiplexing control information into a data area according to an embodiment of the present invention.

Referring to FIG. 15, a method of multiplexing control information in a data area by the base station 1400 includes resource elements of at least two subcarriers adjacent to or not adjacent to a data area of at least one slot of two slots of a resource block pair. Allocating the control information of the at least two terminals to the terminal (S1510) and transmitting such control information to the terminals through the time-frequency resources (S1520).

As described with reference to FIGS. 2 to 13, in the step of allocating control information (S1510), the base station 1400 may allocate control information by frequency division, frequency and time division, and a DM-RS (DeModulation Reference Signal). Such control information may be allocated except for a resource element to which a signal is allocated. In addition, the base station 1400 allocates control information of two terminals by time-division by slot unit in the data area, and provides control information of a terminal using a larger capacity of data through PDSCH among control information of the two terminals. It may be allocated to a slot that is advanced in the time domain. The RB pair may form a control region in a symbol within the second, and the RB pair may exist only in the data region without the control region. The number of terminals allocated by the base station 1400 may be 2 to 8.

In the above-described embodiments of the present invention, embodiments of allocating control information of UEs to resource elements divided into slots and subcarriers of a resource block pair have been described. Hereinafter, an embodiment of assigning an index to resource elements in a resource block pair and allocating control information to groups of resource elements having the same index will be described.

First, the unit to which control information is allocated in the control area will be described. In 3GPP, the basic unit of a control channel is a resource element group (REG) consisting of four resource elements (REs). The REG is composed of four consecutive REs on the frequency axis in which there is no reference signal. The PCFICH is composed of a total of four REGs and transmits a total of two bits indicating the number of OFDM symbols in which the PDCCH exists from 1 to 3. PHICH consists of 3 REGs and transmits Ack / Nack information for Hybrid-ARQ.

The PDCCH is composed of 9-72 REGs according to a Downlink Control Information (DCI) format, which is reception control information of the UE, and an aggregation level for increasing reliability of the PDCCH. The reason why at least 9 REGs are needed is that up to 70 bits of information can be transmitted through DCI format. Since one RE is modulated by QPSK and transmits 2 bits, 35 REs are required, so 36 REs = 9 REGs is the minimum unit. The PDCCH has a CCE (control channel element) composed of nine REGs as a basic unit.

Similarly, resource element grouping may be performed to allocate control information in the data area. In other words, an eREG may be formed by grouping a plurality of resource elements in a data area, and an eCCE configured of the plurality of eREGs may be formed. Control information allocated to the data area may be allocated to the eCCE as a basic unit.

The eREG can be assigned to resource elements in the data area and can be grouped according to the characteristics of the index assigned to each resource element.

FIG. 16 illustrates an example of assigning an index to a resource element in an NCT resource block pair in which a control region does not exist and only a data region exists.

Referring to FIG. 16, in the same symbol region, each resource element is sequentially indexed from 0 according to frequency, and when indexing in one symbol region is completed, the next symbol region adjacent to or closest to the last indexed region is assigned. An index can be assigned to an entire resource element by continuously indexing the resource element. In this case, indexes from 0 to 15 are assigned to each resource element, and after 15 times, indexes are sequentially assigned from 0 again.

However, an index may not be assigned to a resource element to which a DM-RS is allocated.

17 shows another example of assigning an index to a resource element in an NCT resource block pair in which a control region does not exist and only a data region exists.

Referring to FIG. 17, in the same symbol region, each resource element is sequentially indexed from 1 according to frequency, and when indexing is completed in one symbol region, the index is assigned in the same direction as all symbol regions in the next symbol region. In this way, an index can be assigned to all resource elements. In this case, indexes 1 to 16 are assigned to each resource element, and after 16, indexes are sequentially assigned from 1 again.

However, an index may not be assigned to a resource element to which a DM-RS is allocated.

The index assigned to the resource element is described as a number corresponding to 0 to 15 in FIG. 16 and a number corresponding to 1 to 16 in FIG. 17, but the reverse is also possible and may be 16 consecutive numbers.

As shown in FIG. 16 or 17, when indexes are assigned to resource elements in a resource block pair, resource elements having the same index among these resource elements may be grouped into one eREG.

18 through 19 illustrate examples of determining the same index as one resource element group for resource elements assigned an index in an NCT resource block pair in which a control region does not exist and only a data region exists.

Referring to FIG. 18, one resource block pair includes 14 symbols, and DM-RSs are allocated to 12 resource elements in the first and second symbols at the end of each slot. In such resource block pairs, indexes are assigned to each resource element except for the resource element to which the DM-RS is allocated, and as shown in the figure, resource elements having the same index number 1 form a group. . The resource element group (eREG) including the resource element with index 1 includes all nine resource elements.

Referring to FIG. 19, one resource block pair includes 12 symbols, and DM-RSs are allocated to each of eight resource elements in the first and second symbols at the end of each slot. In such resource block pairs, indexes are assigned to each resource element except for the resource element to which the DM-RS is allocated, and as shown in the figure, resource elements having the same index number 1 form a group. . The resource element group (eREG) including the resource element with index 1 includes all eight resource elements.

When the eREG is formed in this way, 16 eREGs are formed in one resource block pair. Each eREG can be reindexed, with the index of each eREG being cyclically shifted to one of {1, 3, 5, 7, 11, 13} per pair of resource blocks to improve frequency diversity. Can be. In addition, the index of each eREG may be cyclic shifted every subframe. The cyclic shift can be determined by selecting up / down.

The control channel element (eCCE) may be configured again with a plurality of eREGs. As a word corresponding to a control channel element (CCE) in the control region, the control channel element in the data region may be referred to as eCCE.

The eCCE may consist of four eREGs. In this case, since 16 eREGs are formed in one resource block pair, four eCCEs may be formed in one resource block pair. Of course, the eCCE may consist of eight eREGs in addition to four eREGs.

The eCCE may be composed of four eREGs in which indexes of resource elements constituting the eREG are consecutive. In terms of the arrangement of resource elements, the resource element indexes constitute one eCCE in four consecutive groups (eREG). On the contrary, the eCCE may be configured of four eREGs having the same indexes of the resource elements constituting the eREG divided by four.

FIG. 20 illustrates an embodiment in which control information is allocated to four terminals for a resource block pair divided into resource element groups in a frequency division duplex (FDD) based communication.

Referring to FIG. 20, control information is allocated in units of four consecutively contiguous resource element indexes. For example, the control information for UE 1 includes resource element groups having indices of 1, 2, 3, and 4, respectively. is assigned to an eCCE containing (eREG).

FIG. 21 illustrates an embodiment in which control information is allocated to four terminals for a resource block pair divided into resource element groups in a TDD-based communication.

Referring to FIG. 21, control information is allocated in units of four consecutively contiguous resource element indexes. For example, the control information for UE 2 includes resource element groups having indices of 5, 6, 7, and 8, respectively. is assigned to an eCCE containing (eREG).

22 is an internal block diagram of a base station according to another embodiment of the present invention.

Referring to FIG. 22, the base station 2200 repeats 16 numbers in a resource block pair with frequency priority to control channel elements (eCCEs) configured of at least two or more groups of resource elements having the same indexes for resource elements indexed. It may include a resource allocator 2210 for allocating control information of at least two terminals to enhanced control channel elements, and a transmitter 2220 for transmitting such control information to the terminals through time-frequency resources.

As described with reference to FIGS. 16 through 21, the resource allocator 2210 may allocate control information in units of four groups of resource element indices consecutively adjacent to each other. In addition, a resource block pair may exist only in the data region without a control region.

23 is a flowchart illustrating a method of multiplexing control information into a data area according to another embodiment of the present invention.

Referring to FIG. 23, a method of multiplexing control information in a data area by the base station 2200 includes repeating 16 numbers in a resource block pair with frequency priority and at least one of resource elements having the same index with respect to the resource elements indexed. Allocating control information of at least two terminals to enhanced control channel elements (eCCEs) including two or more groups (S2310) and transmitting the control information to the terminals through time-frequency resources. It may include (S2320).

As described with reference to FIGS. 16 through 21, the base station 2200 may allocate control information in units of four groups of which resource element indexes are consecutively adjacent. In addition, a resource block pair may exist only in the data region without a control region.

By multiplexing control information in the aforementioned data area, it is possible to efficiently design a control channel that supports CA, CoMP, DL MIMO, etc., which can improve spectral efficiency in 3GPP LTE / LTE-Advanced. .

Although the embodiments of the present invention have been described with reference to the drawings, the present invention is not limited thereto.

In the above-described embodiments, a method and apparatus for multiplexing control information in a data area in case of a normal CP in which one resource block pair includes 14x12 resource elements is described. However, the present invention is not limited thereto, and one resource block pair is 12x12. The same can be applied to extended CP including resource elements of.

In the above-described embodiment, a resource block pair of an NCT in which a control region does not exist and only a data region is exemplarily described. However, the same applies to existing carriers in which a control region exists. For example, as described above with reference to FIGS. 16 through 21, in the case of NCT, frequency-priority-specific numbers are repeatedly indexed in one resource block pair (PRB pair) and resource elements having the same index are stored in one eREG. After the configuration, two or more eREGs are allocated to control information of one terminal, but it has been described as allocating control information of two or more terminals to one resource block pair.

In this case, in the case of the resource block pair of the existing carrier type in which the control region exists, indexing of the resource elements of the resource block pair is given in the same manner as the NCT, except that the control information of two or more terminals may be allocated except for the resource elements of the control region. have.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and variations 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 falling within the scope of the same shall be construed as falling within the scope of the present invention.

Claims (17)

At least two resource elements of at least two subcarriers adjacent to or not adjacent to the data area of at least one of two slots of a physical resource block pair Allocating control information of terminals; And
And transmitting the control information to the terminals through a time-frequency resource.
The method of claim 1,
In the step of assigning the control information,
And dividing the control information by frequency division or frequency and time division.
The method of claim 1,
In the step of assigning the control information,
A method of multiplexing control information in a data area, wherein the control information is allocated except for a resource element to which a DM-RS (DeModulation Reference Signal) is allocated.
The method of claim 1,
In the step of assigning the control information,
In the data area, time slots are allocated in units of slots to allocate control information of two terminals.
Control information is allocated to a data region, wherein control information of a terminal using a larger capacity of data is allocated to a slot ahead of a time domain among control information of the two terminals through a PDSCH (Physical Downlink Shared Channel). How to multiplex.
The method of claim 1,
The resource block pair multiplexes control information to a data area, characterized in that forming a control area in a symbol within a second.
The method of claim 1,
The resource block pair multiplexing control information to a data area, characterized in that there is no control area and only a data area.
Enhanced Control Channel Element (eCCE) consisting of at least two groups of resource elements having the same index for the resource elements indexed by repeating 16 numbers in frequency-first order in a Physical Resource Block pair Allocating control information of at least two terminals to the terminals; And
And transmitting the control information to the terminals through a time-frequency resource.
The method of claim 7, wherein
In the step of assigning the control information,
And assigning the control information in units of four adjacent groups in which the resource element index is consecutively contiguous.
The method of claim 7, wherein
The resource block pair multiplexing control information to a data area, characterized in that there is no control area and only a data area.
The method of claim 7, wherein
And the index is cyclic shifted for each resource block pair or subframe.
At least two resource elements of at least two subcarriers adjacent to or not adjacent to the data area of at least one of two slots of a physical resource block pair A resource allocation unit for allocating control information of the terminals; And
And a base station multiplexing the control information in a data area including a transmitter for transmitting the control information to the terminals through a time-frequency resource.
12. The method of claim 11,
The resource allocation unit,
And a base station multiplexing the control information in a data area, wherein the control information is allocated by frequency division or frequency and time division.
12. The method of claim 11,
The resource allocation unit,
A base station multiplexes control information in a data area, wherein the control information is allocated except for a resource element to which a DM-RS (DeModulation Reference Signal) is allocated.
12. The method of claim 11,
The resource allocation unit,
In the data area, time slots are allocated in units of slots to allocate control information of two terminals.
Control information is allocated to a data region, wherein control information of a terminal using a larger capacity of data is allocated to a slot ahead of a time domain among control information of the two terminals through a PDSCH (Physical Downlink Shared Channel). Base station multiplexing.
Enhanced Control Channel Element (eCCE) consisting of at least two groups of resource elements having the same index for the resource elements indexed by repeating 16 numbers in frequency-first order in a Physical Resource Block pair A resource allocating unit for allocating control information of at least two terminals to the terminals; And
And a base station multiplexing the control information in a data area including a transmitter for transmitting the control information to the terminals through a time-frequency resource.
16. The method of claim 15,
The resource allocation unit,
And a base station multiplexing the control information in a data area, wherein the resource element index allocates the control information in units of four adjacent groups.
16. The method of claim 15,
And the index is cyclic shifted for each resource block pair or subframe.

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