CN101808408A

CN101808408A - Transmission method and system of downlink control information

Info

Publication number: CN101808408A
Application number: CN201010123836A
Authority: CN
Inventors: 吴欣; 戴博; 曾萍; 左志松
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2010-02-11
Filing date: 2010-02-11
Publication date: 2010-08-18
Anticipated expiration: 2030-02-11
Also published as: WO2011097876A1; CN101808408B

Abstract

The invention discloses a transmission method and system of downlink control information. The transmission method comprises the following steps: a terminal receives the uplink and downlink transmission mode configuration information from a base station, wherein the uplink and downlink transmission mode configured by the uplink and downlink transmission mode configuration information contain downlink control information format; the terminal obtains the downlink control information in accordance with the downlink control information format in the searching space corresponding to the downlink control information format; and the base station is used to transmit the uplink transmission mode to the terminal to instruct different DCIs. Therefore, the flexible configuration of DCI format in the uplink transmission of the terminal can be realized.

Description

Transmission method and transmission system of downlink control information

Technical Field

The present invention relates to the field of mobile wireless communications, and in particular, to a method and a system for transmitting downlink control information.

Background

A Radio Frame (RF) in a Long Term Evolution (LTE) system includes Frame structures of a Frequency Division Duplex (FDD) mode and a Time Division Duplex (TDD) mode, in which:

in the frame structure of the FDD mode, as shown in fig. 1, a 10 millisecond (ms) radio frame is composed of twenty slots (slots) with the length of 0.5ms and the number of 0-19, and the slots 2i and 2i +1 constitute a subframe (subframe) i with the length of 1 ms.

In TDD mode, as shown in fig. 2, a 10ms radio frame is composed of two half-frames (half frames) with a length of 5ms, one half-frame includes 5 subframes with a length of 1ms, and subframe i is defined as 2 slots 2i and 2i +1 with a length of 0.5 ms.

In both of the above frame structures, for a standard cyclic Prefix (Normal CP), a slot contains 7 symbols with a length of 66.7 microseconds (us), wherein the CP length of the first symbol is 5.21us, and the length of the remaining 6 symbols is 4.69 us; for Extended Cyclic Prefix (Extended CP), one slot contains 6 symbols, and the CP length of all symbols is 16.67 us.

The version number of LTE corresponds to R8(Release 8), the version number corresponding to the added version is R9(Release 9), and for future LTE-Advance, the version number is R10(Release 10). The following 3 downlink physical control channels are defined in LTE:

(1) a Physical downlink control format Indicator Channel (PCFICH); 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, and the frequency position of the first OFDM symbol is determined by the system downlink bandwidth and the cell Identity (ID);

(2) a Physical hybrid automatic Retransmission Request Indicator Channel (PHICH); the PHICH is used to carry acknowledgement/negative-acknowledgement (ACK/NACK) feedback information of uplink transmission data. The number and time-frequency position of the PHICH can be determined by a system message and a cell ID in a Physical Broadcast Channel (PBCH) of a downlink carrier where the PHICH is located;

(3) a Physical Downlink Control Channel (PDCCH); the PDCCH is used for carrying Downlink Control Information (DCI), and includes: uplink and downlink scheduling information, and uplink power control information.

The formats of the downlink control information DCI (DCI format, abbreviated as DCIF) are divided into the following: DCI format0, DCI format 1A, DCIformat 1B, DCI format 1C, DCI format 1D, DCI format2A, DCI format 3, and DCI format 3A; wherein:

1) DCI format0 is used to indicate scheduling of a Physical Uplink Shared Channel (PUSCH);

2) the DCI format 1, the DCI format 1A, the DCI format 1B, the DCI format 1C and the DCI format 1D are used for different modes of scheduling a PDSCH code word;

3) the DCI format2, the DCI format2A and the DCI format 2B are used for different modes of space division multiplexing;

4) the DCI format 3 and the DCI format 3A are used for different modes of a power Control command for a Physical Uplink Control Channel (PUCCH) and a PUS CH.

The UE receives PDSCH data transmissions via a transmission mode (transmission mode) that is semi-static for higher layer signaling (semi-static) and is set to be based on the PDCCH of the Common (Common) and user equipment-Specific (UE-Specific) search spaces as indicated by:

mode 1: a single antenna port; port 0(Single-antenna port; port 0)

Mode 2: transmission diversity (Transmit diversity)

Mode 3: open-loop spatial multiplexing (Open-loop spatial multiplexing)

Mode 4: closed-loop spatial multiplexing (Closed-loop spatial multiplexing)

Mode 5: multi-user multiple input multiple output (Multi-user MIMO)

Mode 6: closed loop Rank 1 precoding (Closed-loop Rank 1 precoding)

Mode 7: a single antenna port; port 5(Single-antenna port; port 5)

Mode 8: double-layer transmission; ports 7and 8(dual-layer transmission; ports 7and 8).

If the UE is set by the higher layer to perform PDCCH decoding with Cyclic Redundancy Check (CRC) scrambled with cell radio Network Temporary Identifier (C-RNTI), the UE should decode the PDCCH and all related PDSCHs according to the corresponding combinations defined in table 1:

TABLE 1

If the UE is set by the higher layer to perform PDCCH decoding with CRC scrambled with Semi-persistent Scheduled Cell Radio network temporary Identifier (SPS C-RNTI), the UE should decode PDCCH and all related PDSCHs according to the corresponding combinations defined in table 2 below:

TABLE 2

In Release 8 of LTE, no multi-antenna input and output (MIMO) technology is involved in uplink transmission, but in the Release 10 requirement research report of LTE-Advanced, it is clear that the technical requirement of LTE-Advanced to support uplink MIMO and possibly to support discontinuous resource allocation technology, at least one uplink transmission mode needs to be added. Meanwhile, a corresponding downlink control information format (DCI format) needs to be defined to support the transmission mode of uplink MIMO, or support both uplink MIMO and uplink discontinuous resource allocation.

At present, there is no clear scheme for how to configure an uplink transmission mode and a related DCIformat to support an uplink MIMO transmission mode, or support both uplink MIMO and uplink discontinuous resource allocation, thereby bringing inconvenience to practical application.

Disclosure of Invention

The present invention mainly aims to provide a method and a system for transmitting downlink control information, so as to at least solve the problem in the related art that a base station cannot configure a DCI format in uplink transmission.

According to an aspect of the present invention, a method for transmitting downlink control information is provided, which includes: a terminal receives uplink and downlink transmission mode configuration information from a base station, wherein the uplink and downlink transmission modes configured by the uplink and downlink transmission mode configuration information comprise a downlink control information format; and the terminal acquires the downlink control information conforming to the downlink control information format in a search space corresponding to the downlink control information format.

Preferably, the base station sends the downlink control information to the terminal according to the configuration information of the uplink and downlink transmission modes.

Preferably, the uplink transmission mode is a first uplink transmission mode, and includes: downlink control information format DCIF 0; or a downlink control information format DCIF0 and a downlink control information format DCIFT; the DCIF0 format is corresponding to a public search space and a user-specific search space, and is used to instruct the terminal to perform single-antenna transmission and configure continuous resources under the single-antenna transmission; the DCIFT format corresponds to a user-specific search space and is used for indicating the terminal to perform single-antenna transmission and discontinuous resource allocation under the single-antenna transmission.

Preferably, the uplink transmission mode is a second uplink transmission mode, and includes: a downlink control information format DCIF0 and a downlink control information format DCIFY; the DCIF0 format is corresponding to a public search space and a user-specific search space, and is used for indicating a terminal to perform single-antenna transmission; the downlink control information format DCIFY corresponds to a user-specific search space, and is used for instructing a terminal to perform single-antenna transmission or multi-antenna transmission, or instructing the terminal to perform multi-antenna transmission.

Preferably, the downlink control information format DCIFY is further used for indicating the discontinuous resource configuration in single-antenna or multi-antenna transmission, or for indicating the discontinuous resource configuration in multi-antenna transmission.

Preferably, the configured downlink transmission mode is at least one of the following modes: mode 1, including downlink control information formats DCIF1A and DCIF1, for single antenna transmission; mode 2, including downlink control information formats DCIF1A and DCIF1, for transmit diversity; mode 3, including downlink control information formats DCIF2A and DCIF1A, for transmit diversity or open loop spatial multiplexing; mode 4, including the downlink control information format DCIF2DCIF1A, for transmit diversity or closed-loop spatial multiplexing; mode 5, including downlink control information format DCIF1DDCIF1A, for transmit diversity or multiple-user multiple-input multiple-output; mode 6, including the downlink control information format DCIF1 bdceif 1A, for transmit diversity or closed-loop precoding; mode 7, including downlink control information formats DCIF1 and DCIF1A, for transmit diversity or single antenna transmission; mode 8, including downlink control information formats DCIF2B and DCIF1A, for dual-layer transmission or single-antenna transmission; mode Z, including the downlink control information format DCIFY1, is used for multi-layer transmission.

Preferably, when the downlink transmission mode is configured as any one of modes 1 to 8, and Z, the configured uplink transmission mode supports the second uplink transmission mode; or only when the downlink transmission mode is configured to be the mode 3, 4, 5, 6, 8 or Z, the configured uplink transmission mode is the second uplink transmission mode; or only when the downlink transmission mode is configured as the mode 3, 4, 8 or Z, the configured uplink transmission mode is the second uplink transmission mode.

Preferably, when the downlink transmission mode is configured as any one of modes 1 to 8, and Z, the configured uplink transmission mode supports the first uplink transmission mode; or when the downlink transmission mode is configured to be the

modes

1, 2 and 7, the configured uplink transmission mode is the first uplink transmission mode; or only when the downlink transmission mode is configured to be the

modes

1, 2, 5, 6 and 7, the configured uplink transmission mode is the first uplink transmission mode.

Preferably, at least two of the downlink control information formats DCIF1, DCIF1A, DCIF1B and DCIF1D are configured to have the same length; or at least one of the downlink control information formats DCIF2, DCIF2A, DCIF2B and DCIFY1 is configured to have the same length as the downlink control information format DCIFY, and the length of the downlink control information format DCIF1A is different from the length of the downlink control information format DCIFY.

Preferably, at least two of the downlink control information formats DCIF1A, DCIF1B and DCIF1D are configured to have the same length; at least one of the downlink control information formats DCIF2, DCIF2A, DCIF2B, and DCIFY1 is configured to have the same length as the downlink control information format DCIFY, and the length of the downlink control information format DCIF1A is different from the length of the downlink control information format DCIFY.

Preferably, at least one of the downlink control information formats DCIF2, DCIF2A, DCIF2B and DCIFY1 is configured to have the same length as the downlink control information format DCIFY, and the length of the downlink control information format DCIF1A is different from the length of the downlink control information format DCIFY.

Preferably, a length of at least one of the downlink control information formats DCIY and DCIT is configured to be different from at least one of lengths of the downlink control information formats DCIF1, DCIF1B, DCIF1D, DCIF2, DCIF2A, and DCIF 2B.

Preferably, the process of the terminal acquiring the downlink control information conforming to the downlink control information format in the search space corresponding to the downlink control information format includes: a base station configures component carriers to be monitored for a terminal; and the terminal acquires the downlink control information conforming to the downlink control information format in the search space of the component carrier to be monitored.

Preferably, the process of configuring the component carrier to be monitored for the terminal by the base station includes: configuring a UE-specific downlink control channel monitoring set, wherein the downlink control channel monitoring set comprises: a component carrier of a PDCCH to be monitored; configuring a carrier-specific downlink control channel monitoring set for each component carrier of the PDCCH to be monitored, wherein the carrier-specific downlink control channel monitoring set is used for representing a component carrier set of the PDCCH to be monitored, which needs to be monitored by the component carrier of the PDCCH to be monitored; or configuring a downlink carrier set specific to the UE, wherein the downlink carrier set includes: a component carrier of a PDSCH to be received; configuring a carrier-specific downlink control channel monitoring set for each component carrier of the PDSCH to be received, wherein the carrier-specific downlink control channel monitoring set is used for representing a component carrier set of the PDCCH to be monitored, which needs to be monitored by the component carrier of the PDSCH to be received, or representing a component carrier set of the PDCCH corresponding to the PDSCH to be received; or configuring a UE-specific downlink control channel monitoring set and a UE-specific downlink carrier set, wherein the UE-specific downlink control channel monitoring set includes: a component carrier of a PDCCH to be monitored; the UE-specific downlink carrier set includes: a component carrier of a PDSCH to be received; sending a PDCCH (physical downlink control channel) corresponding to the PDSCH of each component carrier in the component carriers of the PDCCH to be monitored on the carrier; and configuring a carrier-specific downlink control channel monitoring set for each component carrier in a UE-specific downlink carrier set but not in a component carrier set of the PDCCH to be monitored, wherein the carrier-specific downlink control channel monitoring set is used for indicating the component carrier set which sends the PDCCH corresponding to the PDSCH to be received of the carrier.

The process that the terminal acquires the downlink control information conforming to the downlink control information format in the search space of the component carrier to be monitored comprises the following steps: and detecting downlink control information formats in the search spaces of all the component carriers of the PDSCH to be monitored in sequence until downlink control information conforming to the downlink control information formats is obtained, wherein when the downlink control information formats are detected in the search spaces of the component carriers of the PDSCH to be monitored currently, the downlink control information formats are also detected in the search spaces of the component carriers required to be monitored by the component carriers of the PDSCH to be monitored currently.

Preferably, when the terminal does not receive the uplink transmission mode configuration information, the uplink transmission mode adopted by the terminal is the first uplink transmission mode.

Preferably, according to the uplink and downlink transmission mode configuration information, the terminal UE detects downlink control information formats of three lengths or downlink control information formats of two lengths, or the terminal UE only detects downlink control information formats of two lengths in a search space dedicated to the UE.

According to another aspect of the present invention, there is provided a transmission system of downlink control information, including: the base station comprises the following components: the configuration module is used for setting uplink and downlink transmission mode configuration information, wherein the uplink and downlink transmission modes comprise downlink control information formats; a sending module, configured to send uplink and downlink transmission mode configuration information; a terminal, comprising: a receiving module, configured to receive uplink and downlink transmission mode configuration information; and the acquisition module is used for acquiring the downlink control information which accords with the downlink control information format in the search space corresponding to the downlink control information format.

The invention realizes the following beneficial effects:

1) different DCIs are indicated by the base station sending the uplink transmission mode to the terminal, so that the flexible configuration of the DCI format in the uplink transmission of the terminal is realized;

2) a DCI format for indicating a terminal to carry out multi-antenna transmission is set so as to realize a transmission mode supporting uplink MIMO;

3) the DCI format for instructing the terminal to perform multi-antenna transmission further instructs the base station to perform discontinuous resource configuration on the terminal, so that the base station can support discontinuous resource configuration while supporting the uplink MIMO transmission mode;

4) the DCI formats of the downlink transmission mode are configured to have the same length, so that only two lengths need to be detected during detection, and the stability of the detection times is ensured.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

fig. 1 is a diagram illustrating a frame structure of an FDD mode in the related art;

fig. 2 is a diagram illustrating a frame structure of a TDD mode in the related art;

fig. 3 is a schematic diagram of a transmission system of downlink control information according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a transmission method of downlink control information according to an embodiment of the present invention.

Detailed Description

The invention will be described in detail hereinafter with reference to the accompanying drawings in conjunction with embodiments. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

First, two new DCI formats defined in the embodiments of the present invention are described.

In R8, the UE is semi-statically set by the higher layer to adopt a certain downlink transmission mode, and then detects the corresponding DCI format in the public and UE-specific search spaces. Since R10 needs to support uplink multi-antenna input/output transmission modes, or support both uplink multi-antenna and uplink discontinuous resource allocation, a new uplink transmission mode and related DCI format need to be defined.

In the embodiment of the present invention, a new DCI format may be defined, which is named DCIformat Y, where the DCI format Y may be used to indicate uplink multi-antenna transmission or single-antenna transmission, or only indicate uplink multi-antenna transmission. Further, the DCI format Y is further used to indicate discontinuous resource allocation or continuous resource allocation in single-antenna transmission or multi-antenna transmission, or indicate discontinuous resource allocation or continuous resource allocation in multi-antenna transmission.

In addition, a new DCT format, called DCI format T, may be defined, where the DCI format T may be used to indicate single-antenna transmission and discontinuous resource allocation in single-antenna transmission. Therefore, in R10, when the UE detects the downlink control channel, DCI format Y and DCI format T defined in the embodiment of the present invention need to be considered.

Specifically, if the DCI format Y adopts a

Type

0 or 1 resource allocation scheme, the DCI format Y may indicate discontinuous resource allocation in a multi-antenna or single-antenna transmission scheme; if the Tpye 2 resource allocation scheme is adopted, and both the multi-antenna and single-antenna transmission schemes can be represented as a continuous resource allocation scheme, but if the DCIformat Y represents that one transport block is enabled, the spare bits in another non-enabled transport block can be used to support the discontinuous resource allocation in the single-antenna transmission scheme.

The above-mentioned preferred value of Y is 0A and the above-mentioned preferred value of T is 0B, or the above-mentioned preferred value of Y is 0B and the above-mentioned preferred value of T is 0A.

In R10, the base station sends the downlink control information to the terminal UE according to the configuration of the downlink transmission mode and the uplink transmission mode, and then at the receiving end, the UE detects the corresponding DCI format in the search space dedicated to the public and the UE through the configuration of the downlink transmission mode and the uplink transmission mode, thereby accurately obtaining the downlink control information on the corresponding resource.

The downlink transmission modes described above include modes 1 to 8 in R8 and R9, and a transmission mode Z supporting multi-layer transmission that may be added in the R10 version.

The uplink transmission mode is the newly defined uplink transmission mode in the embodiment of the present invention, and this transmission mode may include only DCI format0 for indicating a single-antenna transmission mode; DCI format0 and DCI format Y may be included to indicate a single-antenna and multi-antenna transmission scheme, or DCI format0 and DCI format T may be included to indicate a single-antenna transmission scheme.

As can be seen from the above, in order to support MIMO (multiple antenna) transmission and discontinuous resource allocation under a single antenna or multiple antennas, the embodiment of the present invention defines the above two DCI formats: DCI format Y and DCI format T.

Fig. 3 is a schematic entity diagram of a transmission system of downlink control information according to an embodiment of the present invention. As shown in fig. 3, the system for transmitting downlink control information includes: a base station 31 and a terminal 32.

The base station 31 includes: a configuration module 311, configured to configure an uplink transmission mode and a downlink transmission mode, where the uplink and downlink transmission modes include a downlink control information format; a sending module 312, configured to send uplink and downlink transmission mode configuration information. Preferably, the base station sends the downlink control information to the terminal according to the configuration of the uplink transmission mode and the downlink transmission mode.

The terminal 32 includes: a receiving module 321, configured to receive uplink and downlink transmission mode configuration information; an obtaining module 322, configured to obtain downlink control information conforming to the downlink control information format in a search space corresponding to the downlink control information format.

For the transmission system, different DCIs are indicated by the base station sending the uplink transmission mode to the terminal, so that the flexible configuration of the DCI format in the uplink transmission of the terminal is realized.

Fig. 4 is a schematic diagram of a transmission method of downlink control information according to an embodiment of the present invention. As shown in fig. 4, the method for transmitting downlink control information in the transmission system in fig. 3 may include the following steps:

s41, the terminal receives the configuration information of the uplink and downlink transmission modes from the base station, wherein, the uplink and downlink transmission modes configured by the configuration information of the uplink and downlink transmission modes comprise the format of downlink control information;

s42, the terminal obtains the downlink control information conforming to the downlink control information format in the search space corresponding to the downlink control information format.

The following describes, by way of example, an uplink transmission mode and specific methods for sending and detecting DCI format Y and DCI format T according to the embodiment of the present invention.

The first embodiment is as follows:

in this embodiment, two uplink transmission modes are defined as follows:

1) uplink transmission mode a:

if the signaling configured by the base station indicates that the uplink transmission mode can only support a single-antenna transmission mode, an uplink transmission mode a is newly defined, which includes DCI format 0. The uplink transmission mode a is used to indicate a transmission mode of a Single-antenna port (Single-antenna port) in a public (Common) and user-specific (UE-specific) search space, which is represented by DCI format 0. Uplink transmission mode a is shown in table 3:

TABLE 3

UE uplink transmission mode	DCI format	Search space	PDCCH corresponding PDSCH transmission scheme
UE uplink transmission mode	DCI format	Search space	PDCCH corresponding PDSCH transmission scheme	Mode A	DCI format0	Common and C-RNTI-defined UE specific	Single antenna port (Single-antenna port)

In this scenario, when the UE detects the downlink control channel, the UE will still perform detection according to the DCI format in R8.

2) Uplink transmission mode B:

if the signaling configured by the base station indicates that the uplink transmission mode can support both single-antenna transmission and uplink multi-antenna transmission, or both uplink multi-antenna transmission and uplink discontinuous resource allocation, newly defining an uplink transmission mode B, which includes: DCI format0 and DCI format Y.

As a preferred mode, the uplink transmission mode B is used to indicate a transmission mode of a Single-antenna port (Single-antenna port) represented by DCI format0 in a public (Common) search space and a user-specific (UE-specific) search space, and indicate a transmission mode of a Single-user multiple-antenna input and output (SU-MIMO) represented by DCI format Y in a user-specific (UE-specific) search space. Uplink transmission mode B is shown in table 4-1:

TABLE 4-1

By the set DCI format for indicating the terminal to carry out multi-antenna transmission, the transmission mode supporting uplink MIMO (multi-antenna) is realized.

Further, in the transmission mode B, the DCI format Y may be further configured to instruct the base station to perform discontinuous resource configuration on the terminal, so that the base station may support discontinuous resource configuration while supporting an uplink MIMO (multiple antenna) transmission mode.

Or,

as another preferred mode, the uplink transmission mode B is used to indicate a transmission mode of a single-user multiple-antenna input and output (SU-MIMO) or a single-antenna port in a user-specific (UE-specific) search space by using DCI format Y. Uplink transmission mode B is shown in table 4-2:

TABLE 4-2

The spatial multiplexing may also be referred to as multi-antenna port transmission (or referred to as multi-antenna transmission).

In this scenario, when the UE detects the downlink control channel, the UE may perform detection according to the DCI format in R8, or may perform detection according to the relevant DCI format newly defined in R10. The newly defined DCI format refers to a DCI format modified to some extent on the basis of the DCI format in R8.

Further, in the transmission mode B, the DCI format Y may be further configured to instruct the base station to perform discontinuous resource configuration on the terminal, so that the base station may support discontinuous resource configuration while supporting an uplink MIMO (multiple antennas) or single antenna transmission mode.

Further, when the terminal does not receive the uplink transmission mode configuration information, the uplink transmission mode adopted by the terminal is an uplink transmission mode a. That is, the uplink transmission mode defaults to the uplink transmission mode a.

The transmission and detection procedure of DCI is described below.

The UE accurately obtains the downlink control information on corresponding resources on public and UE-specific search spaces through a downlink transmission mode and an uplink transmission mode configured by the base station.

Further, by setting the lengths of the plurality of DCI formats to be the same, when the UE detects the corresponding DCI formats in the public and UE-specific search spaces by configuring the downlink transmission mode and the uplink transmission mode, the UE can accurately obtain the downlink control information on the corresponding resources by only detecting the DCI formats with two lengths, thereby ensuring the stability of the detection times.

The above-mentioned manner of setting the lengths of several DCI formats to be the same may include the following three methods:

1) the method comprises the following steps:

all uplink transmission modes corresponding to the downlink transmission modes (i.e., modes 1 to 8 and mode Z supporting multi-layer transmission) can support an uplink transmission mode a and an uplink transmission mode B, and the uplink transmission mode is configured through signaling of the base station.

When the downlink transmission mode is configured as 1, 2, 5, 6, or 7, it is configured that the UE can only detect DCI formats of two length sizes in the UE-specific search space, so the length size of the DCI format 1 in the

modes

1, 2, 5, 6, and 7and the length sizes of the DCI format 1A, DCI format 1B, and DCI format 1D can be configured to be the same in the UE-specific search space.

Specifically, a certain additional bit is added after DCI format 1, DCI format 1A, DCI format 1B, or DCI format 1D, so that the length sizes of the four are the same. Wherein, 2 bits are required in all of the four DCI formats as bits for distinguishing the four DCI formats. Therefore, the UE only needs to detect the downlink control information format of the DCI format 1(DCI format 1A/1B/1D) length and the DCI format Y length in the UE-specific search space, and the stability of the detection times is ensured.

For Z configured to 3, 4, 8 or support multi-layer transmission in downlink transmission mode, in the UE-specific search space, the length sizes of DCI format2, DCI format2A, DCIformat 2B, and DCI format Y1 are configured to be the same as the length size of newly defined DCIformat Y, where DCI format Y1 is a downlink control information format corresponding to multi-layer transmission in transmission mode Z, and 2 bits are required in all four DCI formats as bits for distinguishing the four DCI formats. Thus, in the UE-specific search space, the UE only needs to detect the downlink control information format of the length of the DCI format 1A and the DCI format Y (2/2A/2B/Y1), and the stability of the detection times is ensured.

2) The second method comprises the following steps:

when only the downlink transmission mode is configured to be 3, 4, 5, 6, 8 and Z, the uplink transmission mode can be configured to be B.

When the downlink transmission mode is configured to be 5 or 6, it is configured that the UE can only detect DCI formats of two length sizes in the UE-specific search space, so that the length sizes of the DCI format 1A in the modes 5 and 6 and the DCI format 1B and the DCI format 1D can be configured to be the same in the UE-specific search space, that is, a certain additional bit is added after the DCI format 1A, the DCI format 1B or the DCI format 1D to make the length sizes of the three be the same. Wherein, 2 bits are required in all three types of DCI formats as bits for distinguishing the three types of DCI formats. Therefore, the UE only needs to detect the downlink control information format of the length of the DCI format 1A (DCIformat 1B/1D) and the length of the DCI format Y in the UE-specific search space, and the stability of the detection times is ensured.

When only the downlink transmission mode is configured to be 1, 2, or 7, the uplink transmission mode may be configured to be a, or any downlink transmission mode may be configured to be the uplink transmission mode a.

3) The third method comprises the following steps:

when only the downlink transmission modes are configured to be 3, 4, 8 and Z, the corresponding uplink transmission mode is B.

When the downlink transmission mode is configured to be 3, 4, or 8 or Z supporting multi-layer transmission, in the UE-specific search space, the length sizes of the DCI format2, the DCI format2A, DCIformat 2B, and the DCI format Y1 are configured to be the same as the length size of the newly defined DCIformat Y, where the DCI format Y1 is a downlink control information format corresponding to multi-layer transmission in the transmission mode Z. Thus, in the UE-specific search space, the UE only needs to detect the downlink control information format of the length of the DCI format 1A and the DCI format Y (2/2A/2B/Y1), and the stability of the detection times is ensured.

When only the downlink transmission modes are configured to be 1, 2, 5, 6 and 7, the uplink transmission mode can be configured to be a, or any downlink transmission mode can be configured to be a.

Example two

In this embodiment, the uplink transmission mode is indicated by signaling configured by the base station. There are two modes as follows:

1) uplink transmission mode a:

if the signaling configured by the base station indicates that the uplink transmission mode can only support a single-antenna transmission mode, newly defining an uplink transmission mode a, which includes: DCI format0 and DCI format T. The uplink transmission mode a is used to indicate a transmission mode of a Single-antenna port (Single-antenna port) in a public (Common) and user-specific (UE-specific) search space by using DCI format 0; in a user-specific (UE-specific) search space, a DCI Format T is used to represent a transmission mode of a single antenna port, and discontinuous resource allocation is supported. Uplink transmission mode a is shown in table 5:

TABLE 5

Further, in the transmission mode a, the DCI format T may be further configured to instruct the base station to perform discontinuous resource configuration on the terminal, so that the base station may support discontinuous resource configuration while supporting the uplink single-antenna transmission mode.

2) Uplink transmission mode B:

if the signaling configured by the base station indicates that the uplink transmission mode can support both single-antenna transmission and uplink multi-antenna transmission, or both uplink multi-antenna and uplink discontinuous resource allocation, newly defining an uplink transmission mode B, which includes: DCI format0 and DCI format Y.

As a preferred mode, the uplink transmission mode B is used to indicate a transmission mode of a Single-antenna port (Single-antenna port) represented by DCI format0 in a public (Common) search space and a user-specific (UE-specific) search space, and indicate a transmission mode of a Single-user multiple-antenna input and output (SU-MIMO) represented by DCI format Y in a user-specific (UE-specific) search space. Uplink transmission mode B is shown in table 6-1:

TABLE 6-1

Or,

as another preferred mode, the uplink transmission mode B is used to indicate a transmission mode of a single-user multiple-antenna input and output (SU-MIMO) or a single-antenna port in a user-specific (UE-specific) search space by using DCI format Y. Uplink transmission mode B is shown in table 6-2:

TABLE 6-2

The transmission and detection procedure of DCI is described below.

Further, by setting the lengths of the plurality of DCI formats to be the same, the downlink control information can be accurately obtained on the corresponding resource only by detecting the DCI formats of three lengths, thereby ensuring the stability of the detection times.

Specifically, in a public search space, detection can be performed according to the detection method and DCI format in R8; in the UE-specific search space, the length sizes of DCI format 1A and DCI format0 are the same, and the initial states of the length sizes of DCI formats in other downlink transmission modes and uplink transmission modes are different.

In this embodiment, the DCI format of the downlink transmission mode in the UE-specific search space is set to be DCI format 1A and DCI format H (where H refers to any one of downlink transmission modes 1 to 8 and DCI format 1/2/2a/2B/1D/1B in downlink transmission mode Z, etc.), and the DCI format of the uplink transmission mode in the UE-specific search space is set to be DCI format0 and DCI format G (where G refers to DCI format T and DCI format Y in uplink transmission mode a or B).

In this way, in the UE-specific search space, only DCIformat (i.e., DCI format0, DCI format H, and DCI format G) with three lengths needs to be detected, the downlink control information can be accurately obtained on the corresponding resource, so that the stability of the detection times is ensured.

Particularly, when the length sizes of the DCI format H and the DCI format G are the same, one bit needs to be added in a certain method for distinguishing, so that the length sizes of the two are not the same.

In the above embodiment, according to the uplink and downlink transmission mode configuration information, the terminal detects downlink control information formats with three lengths or downlink control information formats with two lengths in a search space dedicated to the UE, or the terminal UE only detects downlink control information formats with two lengths in a search space dedicated to the UE.

It is further illustrated that two scenarios of detecting dciformation with three length sizes and detecting DCI format with two length sizes exist in the UE detection process.

Further, the UE in the initial state only needs to detect dciformates with two length sizes, that is, only one DCI format for uplink is needed, and after the base station signaling configuration, the UE starts to detect DCI formats with three length sizes.

Therefore, the downlink control information can be accurately obtained on the corresponding resources, and the stability of the detection times is ensured.

Example three:

in the LTE-Advance system, a carrier aggregation scenario needs to be supported, and in such a scenario, a certain component carrier needs to monitor PDCCHs of multiple other component carriers. The present embodiment proposes a method to determine other component carriers that each component carrier needs to monitor, so as to determine uplink and downlink transmission modes on each component carrier.

Specifically, the process of the terminal acquiring the downlink control information conforming to the downlink control information format in the search space corresponding to the downlink control information format includes:

1) a base station configures component carriers to be monitored for a terminal;

2) and the terminal acquires the downlink control information conforming to the downlink control information format in the search space of the component carrier to be monitored.

The process that the base station configures the component carrier to be monitored for the terminal comprises the following steps:

1) configuring a UE-specific downlink control channel monitoring set, wherein the downlink control channel monitoring set comprises: a component carrier of a PDCCH to be monitored;

configuring a carrier-specific downlink control channel monitoring set for each component carrier of the PDCCH to be monitored, wherein the carrier-specific downlink control channel monitoring set is used for representing a component carrier set of the PDCCH to be monitored, which needs to be monitored by the component carrier of the PDCCH to be monitored;

or,

2) configuring a downlink carrier set proprietary to the UE, wherein the downlink carrier set comprises: a component carrier of a PDSCH to be received;

configuring a carrier-specific downlink control channel monitoring set for each component carrier of the PDSCH to be received, wherein the carrier-specific downlink control channel monitoring set is used for representing a component carrier set of the PDCCH to be monitored, which needs to be monitored by the component carrier of the PDSCH to be received, or representing a component carrier set of the PDCCH corresponding to the PDSCH to be received;

or,

3) configuring a UE-specific downlink control channel monitoring set and a UE-specific downlink carrier set, wherein the UE-specific downlink control channel monitoring set comprises: a component carrier of a PDCCH to be monitored; the UE-specific downlink carrier set includes: a component carrier of a PDSCH to be received;

sending a PDCCH (physical downlink control channel) corresponding to the PDSCH of each component carrier in the component carriers of the PDCCH to be monitored on the carrier;

and configuring a carrier-specific downlink control channel monitoring set for each component carrier in a UE-specific downlink carrier set but not in a component carrier set of the PDCCH to be monitored, wherein the carrier-specific downlink control channel monitoring set is used for indicating the component carrier set which sends the PDCCH corresponding to the PDSCH to be received of the carrier.

The process that the terminal acquires the downlink control information conforming to the downlink control information format in the search space of the component carrier to be monitored comprises the following steps:

detecting the downlink control information format on the search space of all the component carriers of the PDSCH to be monitored in sequence until the downlink control information conforming to the downlink control information format is obtained, wherein,

when the downlink control information format is detected in the search space of the component carrier of the current PDSCH to be monitored, the downlink control information format is also detected in the search space of the component carrier which needs to be monitored by the component carrier of the current PDSCH to be monitored.

By the method, the terminal performs DCI format detection on the search space of the component carrier configured by the base station so as to acquire the downlink control information conforming to the downlink control information format.

From the above description, it can be seen that the present invention achieves the following technical effects:

It will be apparent to those skilled in the art that the modules or steps of the present invention described above may be implemented by a general purpose computing device, they may be centralized on a single computing device or distributed across a network of multiple computing devices, and alternatively, they may be implemented by program code executable by a computing device, such that they may be stored in a storage device and executed by a computing device, and in some cases, the steps shown or described may be performed in an order different than that described herein, or they may be separately fabricated into individual integrated circuit modules, or multiple ones of them may be fabricated into a single integrated circuit module. Thus, the present invention is not limited to any specific combination of hardware and software.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for transmitting downlink control information is characterized by comprising the following steps:

a terminal receives uplink and downlink transmission mode configuration information from a base station, wherein the uplink and downlink transmission modes configured by the uplink and downlink transmission mode configuration information comprise a downlink control information format;

and the terminal acquires the downlink control information conforming to the downlink control information format in a search space corresponding to the downlink control information format.

2. The transmission method according to claim 1, wherein the base station sends the downlink control information to the terminal according to the configuration information of the uplink and downlink transmission modes.

3. The transmission method according to claim 1, wherein the uplink transmission mode is a first uplink transmission mode, which comprises:

downlink control information format DCIF 0; or

The downlink control information format DCIF0 and the downlink control information format DCIFT; wherein,

the DCIF0 corresponds to a public search space and a user-specific search space, and is configured to instruct the terminal to perform single-antenna transmission and perform continuous resource allocation under the single-antenna transmission;

the DCIFT corresponds to a user-specific search space, and is configured to instruct the terminal to perform single-antenna transmission and discontinuous resource allocation under the single-antenna transmission.

4. The transmission method according to claim 1, wherein the uplink transmission mode is a second uplink transmission mode, which comprises:

a downlink control information format DCIF0 and a downlink control information format DCIFY; wherein,

the downlink control information format DCIF0 corresponds to a public search space and a user-specific search space, and is used for instructing the terminal to perform single-antenna transmission;

the DCIFY corresponds to a user-specific search space, and is used for instructing the terminal to perform single-antenna transmission or multi-antenna transmission, or instructing the terminal to perform multi-antenna transmission.

5. The transmission method according to claim 4, wherein the downlink control information format DCIFY is further used for indicating a discontinuous resource configuration in single-antenna or multi-antenna transmission, or for indicating a discontinuous resource configuration in multi-antenna transmission.

6. The transmission method according to claim 3 or 4, wherein the configured downlink transmission mode is at least one of the following modes:

mode 1, including downlink control information formats DCIF1A and DCIF1, for single antenna transmission;

mode 2, including the downlink control information formats DCIF1A and DCIF1, for transmit diversity;

mode 3, including downlink control information format DCIF2A and said DCIF1A, for transmit diversity or open loop spatial multiplexing;

mode 4, including downlink control information format DCIF2 said DCIF1A, for transmit diversity or closed loop spatial multiplexing;

mode 5, including downlink control information format DCIF1D said DCIF1A, for transmit diversity or multiple user multiple input multiple output;

mode 6, including downlink control information format DCIF1B said DCIF1A, for transmit diversity or closed loop precoding;

mode 7, including the downlink control information formats DCIF1 and DCIF1A, for transmit diversity or single antenna transmission;

mode 8, including downlink control information format DCIF2B and the DCIF1A, for dual-layer transmission or single-antenna transmission;

mode Z, including the downlink control information format DCIFY1, is used for multi-layer transmission.

7. The transmission method according to claim 6,

when the downlink transmission mode is configured to be any one of the modes 1 to 8 and Z, the configured uplink transmission mode supports the second uplink transmission mode; or

Only when the downlink transmission mode is configured as the mode 3, 4, 5, 6, 8 or Z, the configured uplink transmission mode is the second uplink transmission mode; or only when the downlink transmission mode is configured as the mode 3, 4, 8 or Z,

the configured uplink transmission mode is the second uplink transmission mode.

8. The transmission method according to claim 6,

when the downlink transmission mode is configured to be any one of the modes 1 to 8 and Z, the configured uplink transmission mode supports the first uplink transmission mode; or

Only when the downlink transmission mode is configured to be the modes 1, 2 and 7, the configured uplink transmission mode is the first uplink transmission mode; or

Only when the downlink transmission mode is configured as the mode 1, 2, 5, 6, 7, the configured uplink transmission mode is the first uplink transmission mode.

9. The transmission method according to claim 6,

configuring lengths of at least two of the downlink control information formats DCIF1, DCIF1A, DCIF1B and DCIF1D to be the same; or

At least one of the downlink control information formats DCIF2, DCIF2A, DCIF2B and DCIFY1 is configured to have the same length as the downlink control information format DCIFY, and the length of the downlink control information format DCIF1A is different from the length of the downlink control information format DCIFY.

10. The transmission method according to claim 6,

configuring lengths of at least two of the downlink control information formats DCIF1A, DCIF1B and DCIF1D to be the same;

11. The transmission method according to claim 6,

12. The transmission method according to claim 6, wherein a length of at least one of the downlink control information formats DCIY and DCIT is configured to be different from at least one of lengths of the downlink control information formats DCIF1, DCIF1B, DCIF1D, DCIF2, DCIF2A and DCIF 2B.

13. The transmission method according to claim 1, wherein the process of the terminal acquiring the downlink control information conforming to the downlink control information format in the search space corresponding to the downlink control information format comprises:

the base station configures a component carrier to be monitored for the terminal;

and the terminal acquires the downlink control information conforming to the downlink control information format in the search space of the component carrier to be monitored.

14. The transmission method according to claim 13, wherein the process of the base station configuring the terminal with the component carrier to be monitored comprises:

configuring a UE-specific downlink control channel monitoring set, wherein the downlink control channel monitoring set comprises: a component carrier of a PDCCH to be monitored;

configuring a carrier-specific downlink control channel monitoring set for each component carrier of the PDCCH to be monitored, wherein the carrier-specific downlink control channel monitoring set is used for indicating a component carrier set of the PDCCH to be monitored, which needs to be monitored by the component carrier of the PDCCH to be monitored;

or,

configuring a downlink carrier set specific to a UE, wherein the downlink carrier set comprises: a component carrier of a PDSCH to be received;

configuring a carrier-specific downlink control channel monitoring set for each of the component carriers of the PDSCH to be received, wherein the carrier-specific downlink control channel monitoring set is used for indicating a component carrier set of a PDCCH to be monitored, which needs to be monitored by the component carrier of the PDSCH to be received, or indicating a component carrier set of a PDCCH corresponding to the PDSCH to be received;

or,

configuring a UE-specific downlink control channel monitoring set and a UE-specific downlink carrier set, wherein the UE-specific downlink control channel monitoring set comprises: a component carrier of a PDCCH to be monitored; the UE-specific downlink carrier set comprises: a component carrier of a PDSCH to be received;

the PDCCH corresponding to the PDSCH of each component carrier in the component carriers of the PDCCH to be monitored is sent on the carrier;

and configuring a carrier-specific downlink control channel monitoring set for each component carrier in the UE-specific downlink carrier set but not in the component carrier set of the PDCCH to be monitored, wherein the carrier-specific downlink control channel monitoring set is used for indicating the component carrier set which sends the PDCCH corresponding to the PDSCH to be received of the carrier.

15. The transmission method according to claim 13, wherein the process of the terminal acquiring the downlink control information conforming to the downlink control information format in the search space of the component carrier to be monitored comprises:

16. The transmission method according to claim 3, wherein the uplink transmission mode adopted by the terminal is the first uplink transmission mode when the terminal does not receive the uplink transmission mode configuration information.

17. The transmission method according to claim 1,

according to the uplink and downlink transmission mode configuration information, the terminal detects downlink control information formats with three lengths or downlink control information formats with two lengths in a search space special for the UE, or the terminal only detects the downlink control information formats with two lengths in the search space special for the UE.

18. A transmission system of downlink control information is characterized in that the transmission system comprises a base station and a terminal, wherein,

the base station, comprising:

the configuration module is used for setting uplink and downlink transmission mode configuration information, wherein the uplink and downlink transmission modes comprise downlink control information formats;

a sending module, configured to send uplink and downlink transmission mode configuration information; the terminal, including:

a receiving module, configured to receive the uplink and downlink transmission mode configuration information;

and the acquisition module is used for acquiring the downlink control information which accords with the downlink control information format in a search space corresponding to the downlink control information format.

19. The transmission system according to claim 18, wherein the uplink transmission mode is a first uplink transmission mode comprising:

downlink control information format DCIF 0; or

20. The transmission system according to claim 18, wherein the uplink transmission mode is a second uplink transmission mode comprising:

21. The transmission system according to claim 20, wherein the downlink control information format DCIFY is further used for indicating a discontinuous resource configuration in single-antenna or multi-antenna transmission, or for indicating a discontinuous resource configuration in multi-antenna transmission.