WO2011015098A1

WO2011015098A1 - Indication method and apparatus of downlink transmission mode

Info

Publication number: WO2011015098A1
Application number: PCT/CN2010/074827
Authority: WO
Inventors: 戴博; 吴欣; 郁光辉; 李卫军
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-08-05
Filing date: 2010-06-30
Publication date: 2011-02-10
Also published as: CN101631374B; CN101631374A

Abstract

An indication method of a downlink transmission mode. The indication method includes: a base station carries Downlink Control Information (DCI) in a physical downlink control channel and transmits them to a terminal, wherein, the downlink transmission mode is indicated by an indicating signaling or by the amount of enabled transmitting blocks and the indication signaling in the downlink control information. An indication apparatus of a downlink transmission mode is also provided. The above method and apparatus can support such transmission modes as double-layer transmission, single layer transmission and transmission diversity, indicate the selecting of transmission mode by specific signaling, and ensure the integrality and backward compatibility of downlink transmission mode and its corresponding DCI Format.

Description

Method and device for indicating downlink transmission mode

Technical field

The present invention relates to the field of mobile wireless communications, and more particularly to a method and apparatus for indicating a downlink transmission mode in a wireless communication system.

Background technique

The radio frame in the Long Term Evolution (LTE) system includes a frame structure of a Frequency Division Duplex (FDD) mode and a Time Division Duplex (TDD) mode. The frame structure of the FDD mode, as shown in Figure 1, a 10 msec (ms) radio frame consists of twenty slots of length 0.5 ms, numbered 0 to 19, and slots 2i and 2i+l. A subframe of length 1 ms (frame ) i. The frame structure of the TDD mode, as shown in FIG. 2, a 10 ms radio frame is composed of two half frames of 5 ms length, one field includes five subframes of length 1 ms, and subframe i is defined as 2 time slots 2i and 2i+1 that are 0.5 ms long. In the above two frame structures, for a normal cyclic prefix (Normal CP, Normal Cyclic Prefix), one slot contains seven symbols with a length of 66.7 seconds (us), and the cyclic prefix (CP) length of the first symbol is 5.21us, the remaining 6 symbols have a length of 4.69 us; for extended cyclic prefix (Extended CP, Extended Cyclic Prefix), one slot contains 6 symbols, and the CP length of all symbols is 16.67 us.

The version number of LTE corresponds to the version (Release, R) 8. The version number corresponding to the added version is

R9 ( Release 9). The following three types of downlink physical control channels are defined in LTE: a Physical Downlink Format Indicator Channel (PCFICH), a Physical Hybrid Automatic Retransmission Request Indicator Channel (PHICH), and a physical downlink. Control Channel (PDCCH, Physical Downlink Control Channel).

The information carried by the PCFICH is used to indicate the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols for transmitting the PDCCH in one subframe, and is sent on the first OFDM symbol of the subframe, where the frequency is located. It is determined by the system downlink bandwidth and the cell identifier (ID, Identity). PHICH is used for ⁷ j Ί々m

information. The number of PHICHs, the time-frequency location may be determined by a system message and a cell ID in a physical broadcast channel (PBCH, Physical Broadcast Channel) of the downlink carrier where the PHICH is located.

The PDCCH is used to carry Downlink Control Information (DCI), and includes: uplink and downlink scheduling information, and uplink power control information. The DCI format is divided into the following types: DCI format 0, DCI format l, DCI format 1A, DCI format 1B, DCI format 1C, DCI format 1D, DCI format 2, DCI format 2A, DCI format 3, and DCI format 3A, etc., wherein the DCI format 0 is used to indicate the scheduling of the Physical Uplink Shared Channel (PUSCH); DCI format l, DCI format 1A, DCI format 1B, DCI format 1C, and DCI format ID are used for one PDSCH code. Different modes of word scheduling; DCI format 2, DCI format 2A is used for different modes of space division multiplexing; DCI format 3, DCI format 3 A is used for power control of physical uplink control channel (PUCCH, Physical Uplink Control Channel) and PUSCH Different modes of instructions.

Among them, the information transmitted by DCI Format 2A is as follows:

RA Header (resource allocation header), I bit is used to indicate the resource allocation header (the resource allocation type type 0 or the type type I). If the downlink bandwidth is less than or equal to 10 PRB (Physical Resource Block) bandwidth, then RB assignment (resource block allocation)

• How to allocate resources for type 0

■

Bits for resource allocation

• How to allocate resources for type 1

■ The “l.g ₂ (P)] bit is used as a header indication to indicate the selected subset of resource blocks.

■ 1 bit is used to indicate the offset of the resource allocation range

■

Bits are used for resource allocation, where the value of P depends on the number of downlink resource blocks

2 bits TPC (Transmit Power Control) for PUCCH 2 bits are used for the Downlink Assignment Index (DAI). This function is only required for the uplink and downlink configuration of the TDD system (TDD only) and is not required in the FDD system.

HARQ Process Number (ID), in the FDD system, 3 bits are used for HARQ (Hybrid Automatic Repeat-reQuest) processes; in TDD system, 4 bits are used for HARQ The number of processes. 1 bit is used to transport the block to code word swap flag. For transport block 1 :

• 5 bits are used to indicate Modulation and Coding Scheme (MCS)

• 1 bit for New Data Indicator (NDI)

· 2 bits are used to indicate Redundancy Version (RV)

For transport block 2:

• 5 bits are used to indicate the modulation and coding scheme (MCS)

• 1 bit for new data indication (NDI)

• 2 bits are used to indicate the redundancy version (RV)

16 bits are used for Cyclic Redundancy Check (CRC), Precoding Matrix Indicator (PMI), and the number of precoding information bits is as shown in Table 1:

Table 1

The physical resources of the PDCCH are transmitted in units of Control Channel Elements (CCEs). The size of one CCE is 9 Resource Element Groups (REGs), that is, 36 Resource Elements, and one PDCCH may be Occupies 1, 2, 4 or 8 CCEs. For the four PDCCH sizes occupying 1, 2, 4, and 8 CCEs, a tree-like aggregation (Aggregation) is used, that is, a PDCCH occupying one CCE can start from any CCE position; a PDCCH occupying two CCEs is from an even number CCE position starts; PDCCH occupying 4 CCEs Starting from an integer multiple of 4 CCE positions; a PDCCH occupying 8 CCEs starts from an integer multiple of CCE positions of 8.

Each aggregation level (Aggregation level) defines a search space (search space), including the common (common) search space and user equipment (UE, User Equipment) proprietary (UE-Specific) search space. The number of CCEs in the entire search space is determined by the number of OFDM symbols and the number of groups of PHICHs occupied by the control region indicated by the PCFICH in each downlink subframe. The UE blindly detects all possible PDCCH code rates in the search space according to the DCI format of the transmission mode.

The UE is semi-statically set by the higher layer signaling to receive the PDSCH data transmission according to the indication of the PDCCH of the UE-Specific search space based on one of the following transmission modes:

Mode 1: Single antenna port; Port 0 ( Single-antenna port; port 0 )

Mode 2: Transmit diversity

Mode 3: Open-loop spatial multiplexing

Mode 4: Closed-loop spatial multiplexing

Mode 5: Multi-user Multiple Input Multiple Output (Multi-user MIMO)

Mode 6: Closed-loop Rank=l precoding (Closed-loop Rank=l precoding)

Mode 7: Single antenna port; Port 5 (Single-antenna port; port 5)

If the UE is configured by the upper layer to perform PDCCH decoding using a Cellular Network Temporary Identifier (C-RNTI, Cell Radio Network Temporary Identifier), the UE should follow the PDCCH decoding. The corresponding combination defined in Table 1 is used to decode the PDCCH and all associated PDSCHs:

DCI format C-RNTI defined single antenna port (Single-ante leg 1 UE specific

Port), port 0 ( port ) 0

DCI format Common and C-RNTI

Transmit diversity mode 1A

2 defined UE specific

DCI format defined by C-RNTI

Transmit diversity 1 UE specific

DCI format Common and C-RNTI

Transmit diversity (Transmit diversity) 1A defined UE specific

Mode 3 Open-loop spatial multiplexing

DCI format defined by C-RNTI

Multiplexing )

2A UE specific

Or transmission diversity (Transmit diversity)

DCI format Common and C-RNTI

Transmit diversity (Transmit diversity) 1A defined UE specific

Mode 4 Closed-loop spatial multiplexing ( Closed-loop

DCI format defined by C-RNTI

Spatial multiplexing ) 2 UE specific

Or transmission diversity (Transmit diversity)

DCI format Common and C-RNTI

Transmit diversity 1A

UE specific defined by mode 5

Multi-user ID UE specific MIMO defined by DCI format C-RNTI

DCI format Common and C-RNTI

Transmit diversity mode 1A

6 defined UE specific

DCI format C-RNTI defined closed loop Rank=1 precoding

IB UE specific (Closed-loop Rank=l precoding) If the number of PBCH antenna ports is 1,

Single antenna port for DCI format Common and C-RNTI ( UE specii port defined by Single-antenna 1A), port 0 ( port O ), mode fc

7

Otherwise transmit diversity (Transmit diversity)

DCI format C-RNTI defined Single-antenna 1 UE specific port ; Port 5 ( port 5 )

Table 1

If the UE is set by the upper layer to perform PDCCH decoding with a semi-persistent scheduling cell radio network temporary identity (SRS C-RNTI, Semi-scrambled CRC), the UE shall decode the PDCCH and all correlations according to the respective combinations defined in Table 3 below. PDSCH: UE PDSCH corresponding PDSCH transmission

DCI format

Transfer mode search space

Program

DCI format Common and C-RNTI Single-antenna port,

UE specific port 0 ( port 0 ) defined by 1A

Mode 1

DCI format C-RNTI defined Single-antenna port,

1 UE specific port 0 ( port 0 )

DCI format Common and C-RNTI

Transmit diversity mode 2 1A defined UE specific

DCI format UE specific by

Transmit diversity 1 C-RNTI

DCI format Common and C-RNTI

Transmit diversity mode 1A

3 defined UE specific

DCI format defined by C-RNTI

Transmit diversity 2A UE specific

DCI format Common and C-RNTI

Transmit diversity mode 1A

4 defined UE specific

DCI format defined by C-RNTI

Transmit diversity 2 UE specific

Mode RNTI

5 DCI format Common and C-transport diversity (Transmit diversity) 1A defined UE specific

Mode NTI

6 DCI format Common and C-R

Transmit diversity (Transmit diversity) 1A defined UE specific

DCI format Common and C-RNTI Single-antenna port,

1A

UE specific port 5 ( port 5 ) defined by mode 7

DCI format C-RNTI defined Single-antenna port,

1 UE specific port 5 ( port 5 )

Table 3: The transmission based on the single antenna port 5 belongs to a non-codebook spatial multiplexing method with rank 1. It also belongs to the application of a single stream beamforming technology; The performance of the codebook transmission mode, a new transmission mode is proposed in the enhanced version R9 of LTE, which belongs to a non-codebook spatial multiplexing mode with rank 2, that is, a two-antenna port using dual-stream Beamforming technology. Transmission.

To this end, a new DCI Format needs to be defined in R9 to support dual stream Beamforming. However, in the prior art solution, the newly defined DCI Format only supports two layers of transmission (single layer transmission) The transmission mode corresponding to the single-antenna port, the two-layer transmission refers to the transmission mode of the two antenna ports corresponding to the dual-stream Beamforming in R9, or the transmission mode of the two-layer transmission and the single-layer transmission at the same time, and the dual-stream Beamforming is still not provided. The technology of DCI Format in the scenario of single-user multi-antenna input and output (SU-MIMO) and multi-user multi-antenna input and output (MU-MIMO), which brings inconvenience to practical applications.

Summary of the invention

The technical problem to be solved by the present invention is to provide a method and an apparatus for indicating a downlink transmission mode, which can represent a two-layer transmission, a single layer transmission, and a transmission diversity transmission mode of a dual-stream beamforming, without increasing signaling overhead and affecting system complexity.

In order to solve the above technical problem, the present invention provides a method for indicating a downlink transmission mode, where the method includes: transmitting, by a base station, downlink control information to a terminal in a physical downlink control channel, and indicating by signaling in the downlink control information. In the downlink transmission mode, or in the downlink control information, the number of the transport block is enabled and the indication signaling indicates the downlink transmission mode.

The above method can also have the following features.

In the step of the base station transmitting the downlink control information to the terminal in the physical downlink control channel, the base station generates the downlink control information by using the row control information format 2A, where the downlink control information format 2A includes the resource allocation header signaling and the resource block. Allocation signaling, transmission power control signaling, downlink allocation index signaling, hybrid automatic repeat request process number signaling, transport block to codeword stream conversion flag signaling, modulation coding mode signaling of the first transport block, first New data indication signaling, first redundancy version signaling, modulation and coding mode signaling of the second transport block, second new data indication signaling, second redundancy version signaling, cyclic redundancy check signaling, and pre- Coded indication signaling;

Alternatively, the base station generates the downlink control information by using a row control information format X, where the downlink control information format X includes resource allocation header signaling, resource block allocation signaling, transmission power control signaling, downlink allocation index signaling, and hybrid Automatic retransmission request process number signaling, transport block to codeword stream conversion flag signaling, modulation coding mode signaling of the first transport block, first new data indication signaling, first redundancy version signaling, second transmission Modulation and coding mode signaling of the block, second new data indication signaling, second redundancy version signaling, and cyclic redundancy check signaling. The foregoing method may further be characterized in that: in the downlink control information, the downlink transmission mode is indicated by the indication signaling, or the step of the downlink transmission mode is indicated by the number of the transmission block and the indication signaling in the downlink control information. in,

When the base station indicates that the first transport block and the second transport block are both enabled by the downlink control information, the downlink transmission mode is indicated as a two-layer transmission mode, and the base station indicates the first transport block and the second transmission by using downlink control information. When one of the transport blocks in the block is enabled, the indication signaling is used to indicate that the downlink transmission mode is a single layer transmission mode or a transmission diversity mode.

The foregoing method may further have the following feature: the indication signaling is a corresponding new data indication signaling in the transport block that is not enabled, or the label signaling is converted to a transport block to a codeword stream. The foregoing method may further be characterized in that: in the downlink control information, the downlink transmission mode is indicated by the indication signaling, or the step of the downlink transmission mode is indicated by the number of the transmission block and the indication signaling in the downlink control information. Medium,

When the base station indicates that the first transport block and the second transport block are both enabled by the downlink control information, the downlink transmission mode is indicated as a two-layer transmission mode, and the base station indicates the first transport block and the second transmission by using downlink control information. When one of the transport blocks in the block is enabled, the indication signaling is used to indicate that the downlink transmission mode is a single layer transmission mode or a transmission diversity mode, and an index of the reference signal when the single layer transmission mode is indicated.

The foregoing method may further be characterized in that: in the downlink control information, the downlink transmission mode is indicated by the indication signaling, or the step of the downlink transmission mode is indicated by the number of the transmission block and the indication signaling in the downlink control information. Medium,

When the base station indicates that the first transport block and the second transport block are both enabled by the downlink control information, the downlink transmission mode is indicated as a single-user two-layer transmission mode, and the base station indicates the first transport block and the first When one of the two transport blocks is enabled, the indication signaling is used to indicate that the downlink transmission mode is a single-user single-layer transmission mode, a multi-user single-layer transmission mode, or a transmission diversity mode.

The above method may also have the following feature, the indication signaling is the transport block-to-codeword stream conversion flag signaling and the corresponding new data indication signaling in the non-enabled transport block. The present invention further provides a downlink transmission mode indication device, where the indication device is configured to transmit downlink control information to a terminal in a physical downlink control channel, and pass the downlink control information The indication signaling is used to indicate the downlink transmission mode, or the downlink transmission mode is indicated by the number of the transport block enable and the indication signaling in the downlink control information.

The foregoing apparatus may further have the following feature: the indication device is configured to generate the downlink control information according to a downlink control information format 2A, where the downlink control information format 2A includes resource allocation header signaling, resource block allocation signaling, Transmission power control signaling, downlink allocation index signaling, hybrid automatic repeat request process number signaling, transport block to codeword stream conversion flag signaling, modulation and coding mode signaling of the first transport block, first new data indication signal Order, first redundancy version signaling, modulation and coding mode signaling of the second transport block, second new data indication signaling, second redundancy version signaling, cyclic redundancy check signaling, and precoding indication signaling Or the indicating device generates the downlink control information by using a row control information format X, where the downlink control information format X includes resource allocation header signaling, resource block allocation signaling, transmission power control signaling, and downlink allocation index. Signaling, hybrid automatic repeat request process number signaling, transport block to codeword stream conversion flag signaling, modulation coding side of the first transport block Signaling, first new data indication signaling, first redundancy version signaling, modulation and coding mode signaling of the second transport block, second new data indication signaling, second redundancy version signaling, and cyclic redundancy Check signaling.

The device may be configured to: the indicating that the downlink transmission mode is a two-layer transmission mode, by using the downlink control information to indicate that the first transmission block and the second transmission block are both enabled. When the downlink control information indicates that one of the first transport block and the second transport block is enabled, the indication signaling is used to indicate that the downlink transmission mode is a single layer transmission mode or a transmission diversity mode.

The foregoing apparatus may further have the following feature, the indication device is configured to use a corresponding new data indication signaling in a transport block that is not enabled, or a transport block to codeword stream conversion flag signaling as the indication signaling .

The device may be configured to: the indication device is configured to indicate that the first transmission block and the second transmission block are both enabled by the downlink control information, thereby indicating that the downlink transmission mode is a two-layer transmission mode, and the downlink control mode is adopted. When the information indicates that one of the first transport block and the second transport block is enabled, the indication signaling is used to indicate that the downlink transmission mode is a single layer transmission mode or a transmission diversity mode, and an index of the reference signal when the single layer transmission mode is indicated. The above device may also have the following features, the indicating device is configured to pass the downlink control letter The signaling indicates that the signaling of the first transport block and the second transport block are both enabled, thereby indicating that the downlink transmission mode is a single-user two-layer transmission mode, and one of the first transport block and the second transport block is indicated by the downlink control information. When the signaling is enabled, the indication signaling is used to indicate that the downlink transmission mode is a single-user single-layer transmission mode, a multi-user single-layer transmission mode, or a transmission diversity mode.

The above apparatus may further have the following feature, the indication means is configured to use the transport block to codeword stream conversion flag signaling and corresponding new data indication signaling in the non-enabled transport block as the indication Signaling.

In the embodiment of the present invention, a new downlink control information format (DCI Format) is defined in order to support the dual-stream Beamforming technology in the LTE-A R9, or a DCI Format in the LTE R8 is modified to indicate a transmission mode related to dual-stream Beamforming. Without adding any signaling overhead and system complexity, it can support not only single-layer transmission and two-layer transmission, but also transmission diversity. At the same time, some signaling is clearly defined in the DCI Format to distinguish these transmission modes, which makes up for the shortcomings of the prior art. On the other hand, the DCI Format defined in the embodiment of the present invention can use one of the DCI formats in the LTE R8, and only needs to change the meaning of one or a few of the bits to achieve good compatibility with the LTE R8.

BRIEF abstract

1 is a schematic diagram of a frame structure of an FDD mode in the prior art;

2 is a schematic diagram of a frame structure of a TDD mode in the prior art;

FIG. 3 is a flowchart of a method for indicating a downlink transmission mode according to the present invention.

Preferred embodiment of the invention

The technical solution of the present invention will be further elaborated below in conjunction with specific embodiments.

The present invention defines a new downlink control information format (DCI Format) for single-user multi-antenna input and output (SU-MIMO), or simultaneously satisfies single-user multi-antenna input and output and multiple for the dual-stream Beamforming technology appearing in R9. In the scenario of multi-antenna input and output (MU-MIMO), the user can represent the transmission mode of two-layer transmission, single-layer transmission and transmission diversity. The single-layer transmission is single-user single-layer transmission, or single-user single-layer transmission and multi-user. Single layer transmission. The present invention provides a downlink transmission mode indication method. As shown in FIG. 3, the method includes: Step 310: The downlink control information is sent to the terminal in the physical downlink control channel, and the downlink transmission mode is indicated in the downlink control information, where In the downlink control information, the downlink transmission mode is indicated by the number of the transmission block and the indication signaling, or the downlink transmission mode is indicated only by the indication signaling;

Step 320: The terminal receives the physical downlink control channel, and receives downlink data according to the downlink transmission mode indicated in the downlink control information.

Wherein, in step 310, DCI Format 2 A or DCI Format X defined by the present invention generates downlink control information. The specific definitions of DCI Format 2A or DCI Format X are shown in Tables 4 and 5.

The definition of DCI Format 2A, which reserves PMI bits (ie, does not use PMI bits), is as shown in Table 4:

Table 4 The definition of DCI Format X is shown in Table 5:

The base station indicates whether the transport block is enabled by defining modulation coding mode (MCS) signaling and redundancy version (RV) signaling in the downlink control information. If the MCS signaling corresponding to a transport block is 0 and the RV signaling is 1, the transport block is not enabled; if the above conditions are not met, the transport block is enabled.

In a single-user multi-antenna input/output (SU-MIMO) scenario, when the base station indicates, by the downlink control information, that two transport blocks are enabled in the downlink transmission, the corresponding downlink transmission mode is a two-layer transmission mode, when there is only one transport block. When the device is enabled, the indication signaling is used to indicate that the downlink transmission mode is a single-layer transmission mode or a transmission diversity mode, where the indication signaling is that the corresponding new data indication signaling in the transport block is not enabled, or the transport block to the codeword is Stream conversion tag signaling.

In another configuration of the newly defined DCI Format, in a single-user multi-antenna input/output (SU-MIMO) scenario, if the base station indicates, by using downlink control information, that only one transport block is enabled in the downlink transmission, further use of the indication signaling Indicates that the downlink transmission mode is a single layer transmission mode or a transmission diversity mode, and an index of a reference signal in a single layer transmission mode, where the indication signaling is that the transmission block is not enabled. Corresponding new data indication signaling and transport block to codeword stream conversion flag signaling, specifically using one of corresponding new data indication signaling and transport block to codeword stream conversion flag signaling in the non-enabled transport block The signaling indicates that the downlink transmission mode is a single layer transmission mode or a transmission diversity mode, and another signaling indicates an index of the reference signal when the single layer transmission mode is used; or, the corresponding new data indication signaling and transmission block in the transmission block are not enabled. The combination of the codeword stream conversion flag signaling indicates that the downlink transmission mode is a single layer transmission mode or a transmission diversity mode, and an index of the reference signal in the single layer transmission mode.

In a single-user multi-antenna input/output (SU-MIMO) scenario and a multi-user multi-antenna input/output (MU-MIMO) scenario, when the base station indicates, by the downlink control information, that both transport blocks are enabled in the downlink transmission, the corresponding downlink is performed. The transmission mode is a single-user two-layer transmission mode. When only one transport block is enabled, the indication signaling is further used to indicate that the downlink transmission mode is a single-user single-layer transmission mode or a multi-user single-layer transmission mode or a transmission diversity mode. Let the corresponding new data indication signaling and transport block to codeword stream conversion flag signaling in the transport block not be enabled. In addition, in step 310, downlink control information may also be generated according to 1A defined in the present invention. The DCI Format 1A adds 1-bit signaling to the DCI Format 1A. When detecting in the UE-specific search space, the 1-bit signaling is used to distinguish whether the transmission is single-layer transmission or transmission diversity. the way.

Embodiment 1

In this embodiment, in the scenario of single-user multi-antenna input and output (SU-MIMO), the newly defined DCI Format 2A/X (indicating DCI Format 2A or DCI Format X, "DCI Format X" represents a newly defined one) DCI format) can be used to indicate the transmission mode of two-layer transmission, single-layer transmission and transmission diversity.

DCI Format 2A/X can correspond to two transport blocks, when both transport blocks are enabled (enable) (when the modulation and coding scheme (MCS) signaling of a transport block is 0 and the redundancy version (RV) signaling is When 1 indicates that the transport block is not enabled, DCI Format 2A/X indicates two-layer transmission. When only one transport block is enabled, DCI Format 2A/X indicates the transmission mode of single-layer transmission or transmission diversity. Wherein, when DCI Format 2A/X indicates single layer transmission, the corresponding reference signal (pilot) is a reference signal when there is only one layer in the layer of R9.

When only one transport block is enabled, the transport block to codeword swap flag and the Disabled in the DCI Format 2A/X The new data indication (NDI) bits corresponding to the transport block will be vacated (i.e., not used), which correspond to the first signaling bit and the second signaling bit, respectively.

The first signaling bit can be used to indicate whether a single transport or a transmit diversity is transmitted when only one transport block is enabled; it can also be indicated by a second signaling bit. For example: Use "0" to identify the transmission diversity, "Γ, identify the single layer transmission. As shown in Table 6:

Table 6 Alternatively, it is identified by "0" as a single layer transmission, and "1" is identified as transmission diversity.

Through the above description, the definition of DCI Format 2A that reserves PMI bits (i.e., does not use PMI bits) is as shown in Table 4, and the definition of DCI Format X is as shown in Table 5. Wherein, when only one transport block is enabled, the transport block to codeword swap flag signaling of the DCI Format 2A or DCI Format X or the NDI signaling corresponding to the transport block that is not enabled is used. It distinguishes the transmission mode of single layer transmission and transmission diversity.

Embodiment 2

In the embodiment of the single-user multi-antenna input and output (SU-MIMO) scenario, the newly defined DCI Format 2A/X can be used to indicate the transmission mode of two-layer transmission, single-layer transmission, and transmission diversity. In the single layer transmission mode, the reference signal index is also indicated, and the transport block index has a one-to-one correspondence with the reference signal (pilot), and different transport blocks correspond to different reference signals (pilots).

DCI Format 2A/X can correspond to two transport blocks. When both transport blocks are enabled, DCI Format 2A/X represents two layers of transmission; when only one transport block is enabled, DCI Format 2A/X represents a single layer. Transmission or transmission diversity transmission. Wherein, when DCI Format 2A/X indicates single layer transmission, the corresponding reference signal (pilot) may be a user-specific reference signal in R8, that is, a reference signal sent on antenna port 5, or may be a middle layer of R9. When the number is only one layer of the reference signal, the specific reference signal index is indicated by signaling.

Transport block to codeword stream conversion in DCI Format 2A/X when only one transport block is enabled The new data indication (NDI) bits corresponding to the transport block to codeword swap flag bits and the non-disabled transport blocks will be vacated, which correspond to the first signaling bit and the second signaling bit, respectively. Therefore, the first signaling bit may be used to indicate whether only one transport block is enabled, whether it is a single layer transmission or a transmission diversity transmission manner, and the second signaling bit is used to identify a reference signal index corresponding to the single layer transmission; The second signaling bit can also be used to indicate whether the single layer transmission or the transmission diversity is transmitted, and the first signaling bit is used to identify the reference signal index corresponding to the single layer transmission; and the joint coding method can also be used. The first signaling bit and the second signaling bit simultaneously indicate the above state.

For example: For the first signaling bit, use "1" for the transmission diversity and "0" for the single layer transmission. As shown in Table 7:

Table 7 or, with "1" for single-layer transmission, with "0" for transmission diversity.

For the second signaling bit, use "1" to identify the reference signal when the number of layers in R9 is only one layer, and use "0" to identify the user-specific reference signal in R8. As shown in Table 8:

Table 8 or, with the "identification of the user-specific reference signal in R8, with "0" is the reference signal when there is only one layer in the R9.

The first signaling bit and the second signaling bit can be used interchangeably.

The first signaling bit and the second signaling bit can also be jointly encoded, that is, using "00", "01",

"10" and "11" correspond to transmission diversity, respectively, and the corresponding reference signal is R8. The user-specific reference signal and the single-layer transmission and the corresponding reference signal are the three states of the reference signal in the R9 with only one layer. If "00" is used as the transmission diversity, the "01" is used as the single layer transmission and the corresponding reference signal is the user-specific reference signal in R8. The "10" is used as the single layer transmission and the corresponding reference signal is R9. The middle layer has only one layer of reference signal, and "11" is reserved. As shown in Table 9:

Table 9 or, in other combinations, is used to identify. The above examples are only examples and are not intended to limit the use of the first signaling bits and the second signaling bits.

Through the above description, the definition of DCI Format 2A that reserves PMI bits (i.e., does not use PMI bits) is as shown in Table 4, and the definition of DCI Format X is as shown in Table 5. Wherein, when a transport block is enabled, the transport block to codeword swap flag bit and the NDI bit corresponding to the unenabled transport block are used to distinguish between single layer transmission and transmission diversity. The transmission mode and the corresponding reference signal index for single layer transmission.

Embodiment 3

In this embodiment, in the scenario of single-user multi-antenna input and output (SU-MIMO) and multi-user multi-antenna input and output (MU-MIMO), the newly defined DCI Format 2A/X can be used to represent single-user two-layer transmission. Single-user single-layer transmission, multi-user single-layer transmission, and transmission diversity transmission.

DCI Format 2A/X can correspond to two transport blocks. When both transport blocks are enabled, DCI Format 2A/X represents single-user two-layer transmission, and when only one transport block is enabled, DCI Format 2A/X Indicates the transmission mode of single-user single-layer transmission, multi-user single-layer transmission, or transmission diversity. among them, When DCI Format 2A/X indicates single layer transmission, its corresponding reference signal (pilot) is the reference signal in R9 corresponding to the enabled transport block.

When only one transport block is enabled, the transport block to codeword swap flag bit in the DCI Format 2A/X is indicated by a new data corresponding to the transport block that is not enabled (Disabled) ( The NDI) bits will be vacated, which correspond to the first signaling bit and the second signaling bit, respectively. Therefore, when only one transport block is enabled, the first signaling bit can be used to indicate whether the single-user single-layer transmission or the single-user transmission diversity is transmitted, and the second signaling bit is used to identify the single-user single layer. The transmission is also a multi-user single-layer transmission; the second signaling bit can also be used to indicate whether the single-user single-layer transmission or the single-user transmission diversity is transmitted, and the first signaling bit is used to identify whether it is a single-user single-layer transmission or Multi-user single layer transmission; the above state can also be indicated by the first signaling bit and the second signaling bit simultaneously by means of joint coding.

For example: For the first signaling bit, use "1" for single-user transmission diversity and "0" for single-user single-layer transmission. As shown in Table 10:

Table 10 or, with "1" for single-user single-layer transmission, with "0" for single-user transmission diversity. For the second signaling bit, a single user single layer transmission is identified by "1" and a multi-user single layer transmission is identified by "0". As shown in Table 11:

Table 11 or, with "1" for multi-user single-layer transmission, with "0" for single-user single-layer transmission. The first signaling bit and the second signaling bit can be used interchangeably. The first signaling bit and the second signaling bit can also be jointly encoded, that is, using "00", "01",

"10" and "11" respectively correspond to single-user transmission diversity, single-user single-layer transmission and multi-user single-layer transmission. For example, "00" is used for single-user transmission diversity, and "01" is used for identification. For single-user single-layer transmission, the "10" is used for multi-user single-layer transmission, and "11" is reserved. As shown in Table 12:

Table 12 or, in other combinations, is used to identify. The above example is only one of them, and is not used to limit the use of the first signaling bit and the second signaling bit.

Through the above description, the definition of DCI Format 2A that reserves PMI bits (i.e., does not use PMI bits) is as shown in Table 4, and the definition of DCI Format X is as shown in Table 5. Among them, when a transport block is enabled, the transport block to codeword stream conversion flag (Transport block to codeword transmission, multi-user single layer transmission and single-user transmission diversity transmission mode).

Embodiment 4

This embodiment will be the DCI described in the first embodiment, the second embodiment and the third embodiment.

The Format 2A/X design was added to the prior art definition of the transmission mode for dual stream Beamforming.

In view of the need to support dual-stream Beamforming technology in R9, it is necessary to define a downlink transmission mode 8 to correspond to dual-layer Beamforming two-layer transmission (ie, two-antenna port transmission), which will include two layers of transmission, single layer transmission, and The transmission mode of the transmission diversity, wherein the double layer beamforming described below corresponds to double layer transmission, and the single layer beamforming corresponds to single layer transmission. At the same time, transmission mode 8 includes two or three DCI formats: DCI Format 1A, DCI Format 2A/X or DCI Format 1 A, DCI Format 2A/X, DCI Format 1 A, where DCI Format 2A/X That is, the DCI Format described in the first embodiment, the second embodiment, and the third embodiment. The following are several different configurations that give Transfer Mode 8:

Configuration one:

Transmission mode 8 contains two DCI formats: DCI Format 1A and DCI Format 2A/X. The DCI Format 1A corresponds to the transmission mode of the transmission diversity, and the DCI Format 2A (or X) corresponds to the transmission mode of the two-layer transmission, the single layer transmission, and the transmission diversity. The corresponding relationship is as shown in Table 13.

Table 13

Configuration two: Transmission mode 8 contains two DCI formats: DCI Format 1A and DCI Format 2A/X. The DCI Format 1 A corresponds to a single layer transmission mode, and the DCI Format 2A (or X) corresponds to a transmission mode of two layers of transmission, single layer transmission, and transmission diversity. The corresponding relationship is shown in Table 14:

Table 14

Configuration three:

Transmission mode 8 contains two DCI formats: DCI Format 1A and DCI Format 2A/X. Among them, DCI Format 1A corresponds to the transmission mode of single layer transmission or transmission diversity, DCI Format 2A

(or X) corresponds to the transmission mode of two layers of transmission, single layer transmission and transmission diversity. The corresponding relationship is shown in Table 15:

DCI Dual-layer beamforming or

UE specific

Format Single-layer beamforming or by C-RNTI

2A/X Transmit diversity

Common

And

Mode 8- PDCCH DCI

UE specific Single-layer beamforming and PDSCH by format 1A

By SPS

SPS C-RNTI with C-RNTI

DCI UE specific Dual-layer beamforming or format by SPS Single-layer beamforming or

2A/X C-RNTI Transmit diversity Table 15

When PDCCH (Physical Downlink Control Channel) and PDSCH (Physical Downlink Shared Channel) are configured by C-RNTI (Cell Radio Network Temporary Identity), DCI Format 1A will correspond to the transmission mode of transmission diversity; and when PDCCH (physical downlink) When the control channel) and the PDSCH (Physical Downlink Shared Channel) are configured by the SPS C-RNTI (Semi-Static Scheduling Cell Radio Network Temporary Identity), the DCI Format 1 A will correspond to a single layer transmission.

Configuration four:

(or X) corresponds to the transmission mode of two layers of transmission, single layer transmission and transmission diversity. The corresponding relationship is shown in Table 16:

DCI Dual-layer beamforming or

UE specific

Format Single-layer beamforming or by C-RNTI

2A/X Transmit diversity

Common

And

Mode 8- PDCCH DCI

UE specific Transmit diversity and PDSCH by format 1A

By SPS

SPS C-RNTI with C-RNTI

2A/X C-RNTI Transmit diversity

Table 16 When PDCCH (Physical Downlink Control Channel) and PDSCH (Physical Downlink Shared Channel) are configured by C-RNTI (Cell Radio Network Temporary Identity), DCI Format 1A will correspond to single layer transmission; and when PDCCH (physical downlink) When the control channel) and the PDSCH (Physical Downlink Shared Channel) are configured by the SPS C-RNTI (Semi-Static Scheduling Cell Radio Network Temporary Identity), the DCI Format 1A will correspond to the transmission mode of the transmission diversity.

Configuration five:

Transmission mode 8 contains two DCI formats: DCI Format 1A and DCI Format 2A/X. Among them, DCI Format 1A corresponds to the transmission mode of single layer transmission and transmission diversity, DCI Format 2A

(or X) corresponds to the transmission mode of two layers of transmission, single layer transmission and transmission diversity. The corresponding relationship is shown in Table 17:

DCI Dual-layer beamforming or

UE specific

Format Single-layer beamforming or by C-RNTI

2A/X Transmit diversity

Common

And

Mode 8- PDCCH DCI Single-layer beamforming or

UE specific

And PDSCH by format 1A Transmit diversity

By SPS

SPS C-RNTI with C-RNTI

2A/X C-RNTI Transmit diversity Table 17

A 1-bit mask is added to the redundancy check to distinguish the transmission mode of single layer transmission and transmission diversity.

Xiji

Transmission mode 8 contains three DCI Formats: DCI Format 1A, DCI Format 1A, and DCI Format 2A/X. Wherein, when the UE performs detection only in the common search space, the DCI Format 1 A corresponds to the transmission mode of the transmission diversity; and when the UE detects only in the UE-specific search space, the DCI Format 1A′ corresponds to the single layer transmission and Transmission mode of transmission diversity; DCI Format 2A (or X) corresponds to the transmission mode of two-layer transmission, single-layer transmission and transmission diversity. The corresponding relationship is shown in Table 18:

Transmission mode DCI

Search space PDCCH corresponding PDSCH transmission scheme format

DCI

Mode 8- PDCCH Common Transmit diversity

Format 1A

And PDSCH DCI

UE specific Transmit diversity; or Single-layer format

Certified by by C-RNTI beamforming

1A'

C-RNTI DCI Dual-layer beamforming or

UE specific

Format Single-layer beamforming or by C-RNTI

2A/X Transmit diversity

Mode 8- PDCCH DCI

Common Transmit diversity format 1A And PDSCH DCI UE specific

Transmit diversity; or Single-layer format by SPS

Configured by SPS beamforming

1A' C-RNTI

C-RNTI DCI UE specific Dual-layer beamforming or format by SPS Single-layer beamforming or

2A/X C-RNTI Transmit diversity Table 18

Here, a DCI Format 1A, DCI Format 1A is newly defined, and 1-bit signaling is added based on the DCI Format 1A. When detecting in the UE-specific search space, the corresponding 1-bit signaling is used to distinguish the corresponding Whether it is a single layer transmission or a transmission diversity transmission method.

In summary, the present invention is directed to the dual-stream Beamforming technology in R9, in single-user multi-antenna input and output (SU-MIMO), or both single-user multi-antenna input and output and multi-user multi-antenna input and output (MU-MIMO). In the scenario, DCI Format 2A/X is defined. The DCI Format 2A/X defined by the present invention can support two-layer transmission, single-layer transmission, and transmission diversity transmission without adding any signaling overhead and without affecting system complexity. It also defines a transmission mode 8, including DCI Format 1A, DCI Format ΙΑ' (optional) and DCI Format 2A/X, to ensure the detection performance and backward compatibility of the PDCCH after supporting the dual-stream Beamforming technology in R9.

Compared with other solutions, the advantage of this solution is that it can support more than one transmission diversity transmission mode, and use explicit signaling to indicate the selection of the transmission mode, and ensure the integrity of the downlink transmission mode and its corresponding DCI Format. And backward compatibility.

One of ordinary skill in the art will appreciate that all or a portion of the steps above may be accomplished by a program to instruct the associated hardware, such as a read-only memory, a magnetic disk, or an optical disk. Alternatively, all or part of the steps of the above embodiments may also be implemented using one or more integrated circuits. Correspondingly, each module/unit in the above embodiment may be implemented in the form of hardware or in the form of a software function module. The invention is not limited to any specific form of combination of hardware and software.

The above is only the embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are intended to be included in the claims of the present invention. Within the scope.

Industrial applicability

The method and device for indicating the downlink transmission mode provided by the present invention can support two layers of transmission, single layer transmission and transmission diversity by using the defined DCI Format 2A/X without adding any signaling overhead and without affecting system complexity. Transmission mode; PDCCH detection performance and backward compatibility after the dual-stream Beamforming technology is supported in R9 by defining the transmission mode 8 including DCI Format 1A, DCI Format ΙΑ ' (optional) and DCI Format 2A/X And the above method and apparatus can support a transmission mode of transmission diversity, and use explicit signaling to indicate pairwise and backward compatibility.

Claims

Claim

1. A method for indicating a downlink transmission mode, comprising:

The base station carries the downlink control information to the terminal in the physical downlink control channel, and indicates the downlink transmission mode by using the indication signaling in the downlink control information, or the number and the indication letter enabled by the transport block in the downlink control information. Let the downlink transmission mode be indicated.

2. The method according to claim 1, wherein in the step of transmitting, by the base station, the downlink control information to the terminal in the physical downlink control channel,

The base station generates the downlink control information by using a row control information format 2A, where the downlink control information format 2A includes resource allocation header signaling, resource block allocation signaling, transmission power control signaling, downlink allocation index signaling, and hybrid automatic weighting. Requesting process number signaling, transport block to codeword stream conversion flag signaling, modulation and coding mode signaling of the first transport block, first new data indication signaling, first redundancy version signaling, second transport block Modulation coding mode signaling, second new data indication signaling, second redundancy version signaling, cyclic redundancy check signaling, and precoding indication signaling;

Alternatively, the base station generates the downlink control information by using a row control information format X, where the downlink control information format X includes resource allocation header signaling, resource block allocation signaling, transmission power control signaling, downlink allocation index signaling, and hybrid Automatic retransmission request process number signaling, transport block to codeword stream conversion flag signaling, modulation coding mode signaling of the first transport block, first new data indication signaling, first redundancy version signaling, second transmission Modulation and coding mode signaling of the block, second new data indication signaling, second redundancy version signaling, and cyclic redundancy check signaling.

The method according to claim 2, wherein the downlink control mode is indicated by the indication signaling in the downlink control information, or the number of the transport block enable and the indication signaling indication are used in the downlink control information. In the step of the downlink transmission mode,

4. The method according to claim 3, wherein the indication signaling is a corresponding new data indication signaling in a transport block that is not enabled, or a transport block-to-codeword stream conversion flag signaling.

The method according to claim 2, wherein the downlink control mode is indicated by the indication signaling in the downlink control information, or the number of the transport block enable and the indication signaling indication are in the downlink control information. In the step of the downlink transmission mode,

The method of claim 2, wherein the downlink control mode is indicated by the indication signaling in the downlink control information, or the number of the transport block enable and the indication signaling indication are used in the downlink control information. In the step of the downlink transmission mode,

The method according to claim 5 or 6, wherein the indication signaling is the transport block to codeword stream conversion flag signaling and the corresponding new data indication signaling in the non-enabled transport block. .

A downlink transmission mode indication device, where the indication device is configured to transmit downlink control information to the terminal in the physical downlink control channel, and indicate the downlink transmission mode by using indication signaling in the downlink control information, or The downlink transmission mode is indicated by the number of the transport block enable and the indication signaling in the downlink control information.

The device according to claim 8, wherein the indication device is configured to generate the downlink control information according to a downlink control information format 2A, where the downlink control information format 2A includes resource allocation header signaling and resource block allocation. Signaling, transmission power control signaling, downlink allocation index signaling, hybrid automatic repeat request process number signaling, transport block to codeword stream conversion flag signaling, modulation coding mode signaling of the first transport block, first new Data indication signaling, first redundancy version signaling, modulation and coding mode signaling of the second transport block, second new data indication signaling, second redundancy version signaling, cyclic redundancy check signaling, and precoding Indication signaling Alternatively, the indication device generates the downlink control information by using a row control information format X, where the downlink control information format X includes resource allocation header signaling, resource block allocation signaling, transmission power control signaling, and downlink allocation index information. Command, hybrid automatic repeat request process number signaling, transport block to codeword stream conversion flag signaling, modulation and coding mode signaling of the first transport block, first new data indication signaling, first redundancy version signaling, Modulation and coding mode signaling, second new data indication signaling, second redundancy version signaling, and cyclic redundancy check signaling of the second transport block.

The device according to claim 9, wherein the indication device is configured to indicate that the first transmission block and the second transmission block are both enabled by the downlink control information, thereby indicating that the downlink transmission mode is a two-layer transmission mode, When the downlink control information indicates that one of the first transport block and the second transport block is enabled, the indication signaling is used to indicate that the downlink transmission mode is a single layer transmission mode or a transmission diversity mode.

11. The apparatus according to claim 10, wherein the indication means is configured to use a corresponding new data indication signaling in a transport block that is not enabled, or a transport block to codeword stream conversion flag signaling as the Indication signaling.

The device according to claim 9, wherein the indication device is configured to indicate that both the first transport block and the second transport block are enabled by using downlink control information, thereby indicating that the downlink transmission mode is a two-layer transmission mode, When the downlink control information indicates that one of the first transport block and the second transport block is enabled, the indication signaling is used to indicate that the downlink transmission mode is a single layer transmission mode or a transmission diversity mode, and the reference signal is indicated when the single layer transmission mode is indicated. index of.

The device according to claim 9, wherein the indication device is configured to indicate that the signaling of the first transport block and the second transport block are both enabled by the downlink control information, thereby indicating that the downlink transmission mode is a single user and two layers. The transmission mode is used to indicate that the signaling of one of the first transport block and the second transport block is enabled by using the downlink control information, and the indication signaling is used to indicate that the downlink transmission mode is a single-user single-layer transmission mode and multi-user single-layer transmission. Mode or transmission diversity mode.

14. The apparatus according to claim 12 or 13, wherein the indication means is configured to use the transport block to codeword stream conversion flag signaling and a corresponding new data indication signal in the inactive transport block Let as the indication signaling.