CN108631988B

CN108631988B - Method and device for data transmission

Info

Publication number: CN108631988B
Application number: CN201710184658.6A
Authority: CN
Inventors: 吴晔; 毕晓艳
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2017-03-24
Filing date: 2017-03-24
Publication date: 2020-12-04
Anticipated expiration: 2037-03-24
Also published as: WO2018171624A1; CN108631988A

Abstract

The application provides a method and a device for data transmission, which can predetermine the mapping relation between the resources of demodulation reference signals and the transmission scheme, and facilitate the receiving end equipment to acquire the transmission schemes of other receiving end equipment. The method comprises the following steps: the sending end equipment carries out precoding on the demodulation reference signal to obtain a precoding demodulation reference signal, and the resource of the demodulation reference signal is associated with the transmission scheme of the data stream corresponding to the demodulation reference signal; and transmitting the pre-coded demodulation reference signal to the first receiving end equipment.

Description

Method and device for data transmission

Technical Field

The present application relates to the field of communications, and more particularly, to a method and apparatus for data transmission.

Background

In Long Term Evolution (LTE) systems and LTE-Advanced (LTE-Advanced) systems, multi-antenna technology is increasingly used for data transmission. The multiple-input multiple-output (MIMO) technology is to use multiple transmitting antennas and multiple receiving antennas in a transmitting end device and a receiving end device, respectively, so that signals are transmitted and received through the multiple antennas of the transmitting end device and the receiving end device.

Currently, a multi-user multiple-input multiple-output (MU-MIMO) technology can support a network device and different terminal devices to transmit different data streams using the same time-frequency resource. With the development of MU-MIMO technology, it becomes possible for a network device to transmit data with different terminal devices by using different transmission schemes.

In some cases it is often advantageous if the terminal device is able to know the transmission scheme of the other terminal device and to demodulate the reference signal. For example, it may be advantageous to reduce the complexity of interference estimation and demodulation. In the current technology, a terminal device can only guess a demodulation reference signal and a transmission scheme used by other terminal devices to transmit data. This means that when the terminal device performs interference estimation, it needs to traverse all demodulation reference signal ports of the cell not used for transmitting data to the terminal device and all demodulation reference signal ports of the neighboring cells, and try various possible transmission schemes to perform interference channel estimation and data demodulation, which greatly increases the complexity of interference estimation and demodulation of the terminal device.

Disclosure of Invention

The application provides a method and a device for data transmission, which can predetermine the corresponding relation between the resources of demodulation reference signals and a transmission scheme, and facilitate receiving end equipment to acquire the transmission schemes of other receiving end equipment.

In a first aspect, a method for data transmission is provided, including:

the method comprises the steps that a sending terminal device carries out precoding on a demodulation reference signal to obtain a precoding demodulation reference signal, and the resource of the demodulation reference signal is associated with the transmission scheme of a data stream corresponding to the demodulation reference signal;

and the sending end equipment sends the pre-coding demodulation reference signal to receiving end equipment.

Therefore, by associating the resources of the demodulation reference signal with the transmission scheme of the data stream corresponding to the demodulation reference signal, the receiving end device can determine the transmission scheme of the corresponding data stream according to the received demodulation reference signal. Therefore, when an interference signal is received, interference estimation can be performed according to the demodulation reference signal and the transmission scheme, and compared with a method of trying different transmission schemes on all unused ports in a traversing manner in the prior art, the interference estimation and demodulation complexity of receiving end equipment is greatly reduced, and time delay brought by data processing is reduced.

In a second aspect, a method for data transmission is provided, including:

the method comprises the steps that a sending terminal device carries out precoding on a demodulation reference signal to obtain a precoding demodulation reference signal, the demodulation reference signal corresponds to a data stream, and the resource of the demodulation reference signal is determined according to the transmission scheme of the data stream;

and sending the pre-coding demodulation reference signal to receiving end equipment.

In the embodiment of the present invention, associating the resource of the demodulation reference signal with the transmission scheme may include: the resources of the demodulation reference signal are directly associated with the transmission scheme, i.e., correspond, or the resources of the demodulation reference signal are indirectly associated with the transmission scheme.

Optionally, the resources of the demodulation reference signals are determined according to a predefined first mapping relation and a transmission scheme of the data stream, where the first mapping relation is used to indicate a correspondence relation between the resources of the multiple demodulation reference signals and at least one transmission scheme.

That is, the first mapping relationship may be statically configured and pre-stored in the sending end device and the receiving end device.

Optionally, before the sending end device performs precoding on the demodulation reference signal, the method further includes:

the sending end device obtains a first mapping relation, the first mapping relation is determined by the network device according to a predefined mapping rule and the resource of the demodulation reference signal required by the currently configured transmission scheme, the first mapping relation is used for indicating the corresponding relation between the resource of a plurality of demodulation reference signals and at least one transmission scheme,

wherein the resource of the demodulation reference signal is determined according to the transmission scheme of the data stream and the first mapping relation. That is, the first mapping relationship may be dynamically or semi-statically configured by the network device and sent to the terminal device, so that both sides can know the first mapping relationship when the network device is used as the sending-end device and the terminal device is used as the receiving-end device, or when the terminal device is used as the sending-end device and the network device is used as the receiving-end device.

Optionally, the network device sends the indication information of the first mapping relationship to the terminal device.

Any one of the transmission schemes may correspond to at least one mapping relationship, for example, the transmission scheme may be: space Frequency Block Code (SFBC), pre-coding polling (precoding), or space division multiplexing (e.g., closed loop space division multiplexing (CLSM)), among others. However, this should not be construed as limiting the embodiments of the present invention in any way. In a specific implementation process, the mapping rule may set resources of corresponding demodulation reference signals for each transmission scheme, or may set resources of corresponding demodulation reference signals only for a part of the transmission schemes, for example, when a transmission scheme includes SFBC, precoding polling and CLSM, resources of corresponding demodulation reference signals may be set for each transmission scheme, or corresponding demodulation reference signals may be set only for two transmission schemes, that is, SFBC and precoding polling, without setting corresponding demodulation reference signals for CLSM. In this case, the network device may preferentially configure resources of demodulation reference signals for both transmission schemes of SFBC and precoded polling, and then configure resources of demodulation reference signals for CLSM. That is, SFBC and precoding polling are directly associated with the resources of the demodulation reference signals, while CLSM is indirectly associated with the resources of the demodulation reference signals.

Therefore, although the receiving end device cannot accurately determine the transmission scheme of the data stream corresponding to each demodulation reference signal directly according to the first mapping relationship, compared with a method of trying different transmission schemes on all unused ports in a traversal manner in the prior art, the blind detection range is reduced, the complexity of interference estimation and demodulation of the receiving end device is reduced to a certain extent, and the time delay caused by data processing is reduced.

In a third aspect, a method for data transmission is provided, including:

receiving end equipment receives a pre-coding demodulation reference signal, wherein the pre-coding demodulation reference signal is obtained by pre-coding a demodulation reference signal by the sending end equipment, and the resource of the demodulation reference signal is associated with the transmission scheme of the data stream corresponding to the demodulation reference signal;

and the receiving end equipment demodulates the data stream according to the pre-coding demodulation reference signal.

In a fourth aspect, a method for data transmission is provided, comprising:

the method comprises the steps that a receiving end device monitors at least one pre-coding demodulation reference signal which is not distributed to the receiving end device, the at least one pre-coding demodulation reference signal is obtained by pre-coding the at least one demodulation reference signal by the sending end device, and each demodulation reference signal corresponds to a data stream;

and the receiving end equipment determines a transmission scheme corresponding to the at least one pre-coding demodulation reference signal based on the incidence relation between the resources of the demodulation reference signal and the transmission scheme.

Therefore, by associating the resources of the demodulation reference signal with the transmission scheme of the data stream corresponding to the demodulation reference signal, the receiving end device can determine the transmission scheme of the corresponding data stream according to the received demodulation reference signal. Therefore, when the interference signal is received, the interference estimation can be carried out according to the demodulation reference signal and the transmission scheme, the complexity of the interference estimation and demodulation of the receiving end equipment is greatly reduced, and the time delay brought by data processing is reduced.

Optionally, the method further comprises:

and the receiving end equipment determines a channel matrix corresponding to at least one pre-coding demodulation reference signal based on the at least one pre-coding demodulation reference signal and the corresponding transmission scheme.

Optionally, the association relationship between the resources of the demodulation reference signal and the transmission schemes includes a first mapping relationship, where the first mapping relationship is used to indicate a correspondence relationship between the resources of the multiple demodulation reference signals and at least one transmission scheme; and

the receiving end device determines a transmission scheme corresponding to the at least one pre-coding demodulation reference signal based on an association relationship between a resource of the demodulation reference signal and the transmission scheme, and the determining includes:

and the receiving end equipment determines a transmission scheme corresponding to the resource of the pre-coding demodulation reference signal as the transmission scheme of the data stream according to a first mapping relation defined in advance.

the receiving end equipment acquires the first mapping relation, wherein the first mapping relation is determined according to a predefined mapping rule and the resources of demodulation reference signals required by the currently configured transmission scheme;

and the receiving end equipment determines the transmission scheme of the data stream according to the first mapping relation and the resource of the pre-coding demodulation reference signal.

That is, the first mapping relationship may be dynamically or semi-statically configured by the network device and sent to the terminal device, so that both sides can know the first mapping relationship when the network device is used as the sending-end device and the terminal device is used as the receiving-end device, or when the terminal device is used as the sending-end device and the network device is used as the receiving-end device.

Any one of the transmission schemes may correspond to at least one mapping relationship, for example, the transmission scheme may be: space Frequency Block Code (SFBC), pre-coded polling, or space division multiplexing, etc. However, this should not be construed as limiting the embodiments of the present invention in any way. In a specific implementation process, the mapping rule may set resources of corresponding demodulation reference signals for each transmission scheme, or may set resources of corresponding demodulation reference signals only for a part of the transmission schemes, for example, when a transmission scheme includes SFBC, precoding polling and CLSM, resources of corresponding demodulation reference signals may be set for each transmission scheme, or corresponding demodulation reference signals may be set only for two transmission schemes, that is, SFBC and precoding polling, without setting corresponding demodulation reference signals for CLSM. In this case, the network device may preferentially configure resources of demodulation reference signals for both transmission schemes of SFBC and precoded polling, and then configure resources of demodulation reference signals for CLSM. That is, SFBC and precoding polling are directly associated with the resources of the demodulation reference signals, while CLSM is indirectly associated with the resources of the demodulation reference signals.

In a fifth aspect, a method for data transmission is provided, which includes:

the network equipment determines a first mapping relation according to a predefined mapping rule and the resources of demodulation reference signals required by the currently configured transmission scheme, wherein the first mapping relation is used for indicating the corresponding relation between the resources of a plurality of demodulation reference signals and at least one transmission scheme;

and the network equipment sends the indication information of the first mapping relation to the terminal equipment.

Optionally, the sending, to the terminal device, the indication information of the first mapping relationship includes:

and the network equipment sends a Radio Resource Control (RRC) message to the terminal equipment, wherein the RRC message carries the indication information of the first mapping relation.

and the network equipment sends a Media Access Control (MAC) -control Cell (CE) to the terminal equipment, wherein the MAC-CE carries the indication information of the first mapping relation.

and the network equipment sends downlink control information DCI to the terminal equipment, wherein the DCI carries the indication information of the first mapping relation.

By carrying the indication information of the first mapping relation in any one of the signaling, the dynamic or semi-static configuration of the first mapping relation is realized.

In a sixth aspect, a method for data transmission is provided, which includes:

the terminal equipment receives indication information of a first mapping relation sent by network equipment, wherein the first mapping relation is used for indicating the corresponding relation between a plurality of demodulation reference signals and at least one transmission scheme;

and the terminal equipment determines the resource of a demodulation reference signal according to the first mapping relation and the transmission scheme of the received data stream, wherein the demodulation reference signal corresponds to the data stream.

Optionally, the receiving, by the terminal device, the indication information of the first mapping relationship sent by the network device includes:

and the terminal equipment receives a Radio Resource Control (RRC) message sent by network equipment, wherein the RRC message carries the indication information of the first mapping relation.

and the terminal equipment receives a Media Access Control (MAC) -control Cell (CE) sent by network equipment, wherein the MAC-CE carries the indication information of the first mapping relation.

and the terminal equipment receives downlink control information DCI sent by the network equipment, wherein the DCI carries the indication information of the first mapping relation.

In a seventh aspect, an apparatus for data transmission is provided, which includes various modules for performing the method for data transmission in any one of the possible implementations of the first to sixth aspects or the first to sixth aspects.

In an eighth aspect, an apparatus for data transmission is provided that includes a processor and a memory. The memory is used for storing a computer program, and the processor is used for calling and running the computer program from the memory so that the apparatus for data transmission executes the method in any one of the possible implementation manners of the first to sixth aspects or the first to sixth aspects.

In a ninth aspect, there is provided a computer program product, the computer program product comprising: computer program code which, when run by an apparatus for data transmission, causes the apparatus for data transmission to perform the method of any of the possible implementations of the first to sixth aspects or the first to sixth aspects described above.

In a tenth aspect, a computer-readable medium is provided, the computer-readable medium storing program code comprising instructions for performing the method of any one of the possible implementations of the first to sixth aspects or of the first to sixth aspects.

Optionally, the resources of the demodulation reference signal include at least one of: ports, scrambling codes, orthogonal codes, and orthogonal sequences.

Optionally, in the downlink transmission, the resource of the demodulation reference signal includes: ports and/or scrambling codes.

Optionally, in uplink transmission, the resource of the demodulation reference signal includes: orthogonal codes or orthogonal sequences.

In particular, the port number may indicate orthogonal codes and time-frequency resources.

Optionally, the mapping rule includes: mapping the index number of the resource of at least one demodulation reference signal to a transmission scheme in sequence from a specific index number according to the sequence from small to large of the index number of the resource of the demodulation reference signal,

wherein the index number of the resource of the demodulation reference signal comprises: port number of the demodulation reference signal, index number (n) of scrambling code identification of the demodulation reference signal_SCID) An index of an orthogonal code of the demodulation reference signal, or an index number of an orthogonal sequence of the demodulation reference signal.

In the present application, an index number may be understood as an identifier for identifying a certain attribute, for example, an index of an orthogonal code, which may also be referred to as an identifier of an orthogonal code, and an index of an orthogonal sequence, which may also be referred to as an identifier of an orthogonal sequence.

Drawings

Fig. 1 is a schematic diagram of a communication system suitable for use with the method and apparatus for data transmission of embodiments of the present invention.

Fig. 2 is a schematic diagram of a downlink physical channel processing procedure adopted in an existing LTE system.

Fig. 3 is a schematic flow chart of a method for data transmission according to an embodiment of the present invention.

Fig. 4 is a schematic diagram illustrating a correspondence relationship between port numbers of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention.

Fig. 5 is another schematic diagram of correspondence between port numbers of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention.

Fig. 6 is another schematic diagram of correspondence between port numbers of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention.

Fig. 7 is a schematic diagram of a correspondence relationship between indexes of scrambling code identifiers of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention.

Fig. 8 is a schematic diagram illustrating a correspondence relationship between port numbers of multiple demodulation reference signals, index numbers of scrambling code identifiers, and at least one transmission scheme according to an embodiment of the present invention.

Fig. 9 shows a schematic diagram of precoding different REs in the same RB.

Fig. 10 is a schematic diagram of a communication system suitable for use in a method for data transmission according to another embodiment of the present invention.

Fig. 11 is a schematic flow chart of a method for data transmission according to another embodiment of the present invention.

Fig. 12 is a schematic diagram illustrating a correspondence relationship between index numbers of orthogonal sequences of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention.

Fig. 13 is a schematic diagram illustrating a correspondence relationship between port numbers of multiple demodulation reference signals, index numbers of orthogonal sequences, and at least one transmission scheme according to an embodiment of the present invention.

Fig. 14 is a schematic flow chart of a method for data transmission according to another embodiment of the present invention.

Fig. 15 is a schematic block diagram of an apparatus for data transmission according to an embodiment of the present invention.

Fig. 16 is a schematic block diagram of an apparatus for data transmission according to another embodiment of the present invention.

Fig. 17 is a schematic block diagram of an apparatus for data transmission according to another embodiment of the present invention.

Fig. 18 is a schematic block diagram of an apparatus for data transmission according to another embodiment of the present invention.

Fig. 19 is a schematic block diagram of an apparatus for data transmission according to an embodiment of the present invention.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

For the understanding of the embodiments of the present invention, a communication system suitable for the embodiments of the present invention will be described in detail with reference to fig. 1. Fig. 1 shows a schematic diagram of a communication system suitable for the method and apparatus for data transmission of the present invention. As shown in fig. 1, the communication system 100 includes a network device 102, and the network device 102 may include a plurality of antennas, e.g.,

antennas

104, 106, 108, 110, 112, and 114. Additionally, network device 102 can additionally include a transmitter chain and a receiver chain, each of which can comprise a plurality of components associated with signal transmission and reception (e.g., processors, modulators, multiplexers, demodulators, demultiplexers, antennas, etc.), as will be appreciated by one skilled in the art.

It should be understood that the network device 102 may be a Base Transceiver Station (BTS) in global system for mobile communications (GSM) or Code Division Multiple Access (CDMA), a Base Station (NodeB, NB) in Wideband Code Division Multiple Access (WCDMA), an evolved Node B (eNB, or eNodeB) in Long Term Evolution (Long Term Evolution, LTE), or a relay Station, an Access Point, or a Radio Remote Unit (RRU), or a network side device in a vehicle-mounted device, a wearable device, and a future fifth-generation communication (5G) network, such as a Transmission Point (TRP), a Base Station, a small Base Station, and the like, which are not specifically limited in this embodiment.

Network device 102 may communicate with a plurality of terminal devices, such as terminal device 116 and terminal device 122. Network device 102 may communicate with any number of terminal devices similar to

terminal devices

116 or 122.

It should be understood that

terminal Equipment

116 or 122 can also be referred to as User Equipment (UE) User Equipment, access terminal, subscriber unit, subscriber station, mobile station, remote terminal, mobile device, User terminal, wireless communication device, User agent, or User Equipment. The terminal device may be a Station (ST) in a Wireless Local Area Network (WLAN), and may be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA) device, a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, and a next-generation communication system, for example, a terminal device in a 5G network or a terminal device in a future-evolution Public Land Mobile Network (PLMN) network, and the like, which are not particularly limited in this embodiment of the present invention.

As shown in fig. 1, terminal device 116 is in communication with

antennas

112 and 114, where

antennas

112 and 114 transmit information to terminal device 116 over forward link 118 and receive information from terminal device 116 over reverse link 120. In addition, terminal device 122 is in communication with

antennas

104 and 106, where

antennas

104 and 106 transmit information to terminal device 122 over forward link 124 and receive information from terminal device 122 over reverse link 126.

In a Frequency Division Duplex (FDD) system, forward link 118 may utilize a different frequency band than that used by reverse link 120, and forward link 124 may utilize a different frequency band than that used by reverse link 126, for example.

As another example, in Time Division Duplex (TDD) systems and full duplex (full duplex) systems, forward link 118 and reverse link 120 may utilize a common frequency band and forward link 124 and reverse link 126 may utilize a common frequency band.

Each antenna (or group of antennas consisting of multiple antennas) and/or area designed for communication is referred to as a sector of network device 102. For example, antenna groups may be designed to communicate to terminal devices in a sector of the areas covered by network device 102. During communication by network device 102 with

terminal devices

116 and 122 over

forward links

118 and 124, respectively, the transmitting antennas of network device 102 may utilize beamforming to improve signal-to-noise ratio of

forward links

118 and 124. Moreover, mobile devices in neighboring cells can experience less interference when network device 102 utilizes beamforming to transmit to

terminal devices

116 and 122 scattered randomly through an associated coverage area, as compared to a manner in which a network device transmits through a single antenna to all its terminal devices.

Network device 102, terminal device 116, or terminal device 122 may be a wireless communication transmitting apparatus and/or a wireless communication receiving apparatus. When sending data, the wireless communication sending device may encode the data for transmission. Specifically, the wireless communication transmitting device may obtain (e.g., generate, receive from other communication devices, or save in memory, etc.) a number of data bits to be transmitted over the channel to the wireless communication receiving device. Such data bits may be contained in a transport block (or transport blocks) of data, which may be segmented to produce multiple code blocks.

Furthermore, the communication system 100 may be a Public Land Mobile Network (PLMN) network or a device to device (D2D) network or a machine to machine (M2M) network or other networks, which is illustrated in fig. 1 for ease of understanding only, and other network devices may be included in the network, which are not shown in fig. 1.

In the embodiment of the present invention, optionally, the sending end device is a network device, and the receiving end device is a terminal device; or, the sending end device is a terminal device, and the receiving end device is a network device.

For convenience of explanation and understanding, a sending end device is taken as a network device, and a receiving end device is taken as a terminal device, in which case, the network device may transmit data with at least one terminal device through the same time-frequency resource.

Fig. 2 is a schematic diagram of a downlink physical channel processing procedure adopted in an existing LTE system. The processing object of the downlink physical channel processing procedure is a codeword, and the codeword is usually a coded (at least including channel coding) bit stream. The code word is scrambled (scrambled) to generate a scrambled bit stream. The scrambled bit stream is subjected to modulation mapping (modulation mapping) to obtain a modulation symbol stream. The modulation symbol stream is mapped to a plurality of symbol layers (also referred to as spatial streams, spatial layers) through layer mapping. The symbol layers are precoded (precoding) resulting in a plurality of precoded symbol streams. The precoded symbol streams are mapped to a plurality of REs through Resource Element (RE) mapping. These REs are then Orthogonal Frequency Division Multiplexing (OFDM) modulated, generating a stream of OFDM symbols. The OFDM symbol stream is then transmitted through an antenna port (antenna port).

By the above processing procedure of the data, space division multiplexing (spatial division multiplexing) or transmit diversity (transmit diversity) can be realized.

Space division multiplexing refers to the reuse of the same frequency band in different spaces. Spatial division multiplexing can be achieved by, for example, using adaptive array antennas to form different beams in different user directions, each beam providing a unique channel without interference from other users. Multiple terminals may transmit using the same time-frequency resources at the same time. Therefore, the frequency spectrum utilization rate and the system data throughput can be greatly improved.

Precoding is an important technique for achieving space division multiplexing. The precoding technique may be to perform pre-processing on a signal at a transmitting end under the condition of a known channel state, that is, to process a signal to be transmitted by using a precoding matrix matched with a channel resource, so that the signal to be transmitted after precoding is adapted to a channel, and complexity of eliminating inter-channel influence at the receiving end is reduced. Therefore, the received Signal quality (e.g., Signal-to-Interference plus Noise Ratio, SINR)) is improved by the pre-coding of the transmitted Signal. Therefore, by adopting the precoding technology, the transmission of the transmitting end equipment and a plurality of receiving end equipment on the same time-frequency resource can be realized, namely, the MU-MIMO is realized.

It should be noted that, in the embodiment of the present invention, for convenience of description, precoding refers to precoding for implementing space division multiplexing without making a specific description. However, it will be appreciated by those skilled in the art that for the precoding referred to herein, if not specifically stated or if not in logical conflict with its actual role or inherent in the related description, it may be more generally described as space division multiplexing precoding.

Transmit diversity improves transmission reliability by redundantly transmitting the original signal (e.g., symbols) in time, frequency, space (e.g., antennas), or various combinations of the three dimensions described above to achieve diversity gain.

Currently, the commonly used transmit diversity includes, for example, but not limited to, space-time diversity (STTD), space-frequency diversity (SFTD), space-frequency block code (SFBC), space-time block code (STBC), time-switched transmit diversity (TSTD), frequency-switched transmit diversity (FSTD), orthogonal diversity (OTD), Cyclic Delay Diversity (CDD), layer interleaving (layer shifting), and other diversity schemes, and diversity schemes obtained by deriving, diversity combining, and space-division multiplexing based on the listed transmit schemes.

In the current protocol, the MU-MIMO only supports that the sending end device and a plurality of receiving end devices transmit data by using the same time-frequency resource and the same transmission scheme (or transmission scheme). It should be noted that the transmission scheme described herein may be a transmission scheme defined in an existing protocol (e.g., LTE protocol), or may be a transmission scheme defined in a related protocol in the future 5G, which is not particularly limited in the present invention. It should be understood that the transmission scheme may be understood as a reference to a technical scheme used for transmitting data, and should not constitute any limitation to the present invention, and the present invention does not exclude the possibility of replacing the transmission scheme by other references in future protocols.

For example, a network device employs Closed Loop Spatial Multiplexing (CLSM) to transmit data to multiple terminal devices simultaneously. However, due to the influence of different environments, different geographical locations, different mobility, and the like of the receiving end devices, the channel environments are also different. For receiving end equipment with a better channel environment, the quality of received signals is probably better by adopting a CLSM transmission scheme; for a receiving end device with a poor channel environment, the received signal quality is poor, and it may be necessary to use transmit diversity to obtain diversity gain.

Therefore, with the development of MU-MIMO technology, it is a possible trend to use different transmission schemes and multiple receiving end devices to transmit data.

Referring to the communication system shown in fig. 1, in downlink transmission, the network device 102 may transmit data with the terminal device 116 based on the transmission scheme of CLSM, and may also pre-process the data transmitted to the terminal device 122 based on the transmit diversity technique, and then transmit the diversity data to the terminal device 122 in a space division multiplexing manner.

In this case, the terminal device (e.g., terminal device 116) is not aware of the transmission scheme of the other terminal devices (e.g., terminal device 122). However, in some cases, it is often advantageous for a terminal device to know the transmission scheme of other terminal devices and the port (port) of a demodulation reference signal (DMRS). For example, the complexity of the terminal device interference estimation may be greatly reduced.

Specifically, still taking fig. 1 as an example, if network device 102 transmits data to terminal device 116 and terminal device 122 simultaneously, it is assumed that the communication system supports transmission of up to 8 DMRS ports (e.g., port #0 to port # 7). For example, network device 102 sends data # a to terminal device 116 via port #0 and port #1, while sending data # B to terminal device 122 via port # 3. While terminal device 116 and terminal device 122 may both receive data # a and data # B, respectively, at the same time. Assuming that the terminal device 116 is the target terminal device, it is necessary for the terminal device 116 to eliminate the interference generated by the data # B to obtain the data # a with better signal quality, so that the pilot channel for transmitting the DMRS and the data channel for transmitting the data between the terminal device 122 and the network device 102 constitute the interference channel of the terminal device 116. In contrast, the pilot channel, in which terminal 116 and network 102 transmit DMRS, and the data channel, in which data is transmitted, form an interference channel for terminal 122.

Here, it should be noted that, in the embodiment of the present invention, the DMRS is defined by a DMRS port, or in other words, defined by DMRS resources. Each DMRS may correspond to one port. It should be understood that DMRS is used as a reference signal for demodulating data, and is only an exemplary signal, and should not be construed as limiting the embodiments of the present invention in any way, and this application does not exclude the possibility that another name may be used in the existing or future protocol instead of DMRS to achieve the same function.

In the prior art, since the terminal device 116 cannot know the transmission scheme of the data # B and the demodulation reference signal port, the terminal device 116 can only blindly assume the transmission scheme of the interfering port, that is, try to receive the demodulation reference signal on each port except the port to which the terminal device is addressed, and traverse various possible transmission schemes on the port on which the demodulation reference signal is received to estimate the interfering channel, which may be referred to as blind detection. That is, the terminal device 116 may attempt to receive the DMRS transmitted by the network device 102 to the terminal device 122 on the remaining six ports except for port #0 and port #1, and in the case of receiving the DMRS, assume one transmission scheme among various possible transmission schemes to estimate a channel matrix of an interference channel, and then obtain an interference noise covariance matrix from the channel matrix of the interference channel, and process the received signal through a reception algorithm. The received signal is processed, for example, using a Minimum Mean Square Error (MMSE) -Interference Rejection Combining (IRC) reception algorithm to attempt to demodulate data # a. If the demodulation is not successful, another transmission scheme needs to be tried again.

It should be noted that, in the embodiment of the present invention, since the demodulation reference signal is precoded, the channel matrix estimated according to the precoded demodulation reference signal is an equivalent channel matrix, and in the embodiment of the present invention, the channel matrices refer to the equivalent channel matrix unless otherwise specified.

On the other hand, in some transmission schemes, for example, SFBC, which needs to implement data transmission through two or more ports, although a channel matrix of an interference channel can be estimated according to precoding vectors of DMRSs, if the transmission scheme is unknown, an interference estimation accuracy obtained by directly calculating an interference noise covariance matrix according to the channel matrix estimated by each DMRS is low, which may finally cause that a demodulated first data stream is erroneous and interference estimation needs to be performed again.

There are also transmission schemes that are precoded based on REs, e.g., precoding round robin (precoding). In this case, if the channel matrix corresponding to each RE is estimated directly from one received DMRS, channel estimation for part of the REs is erroneous. The interference noise covariance matrix derived from this channel matrix is also not suitable for processing the data on each RE. If the channel matrix is used to perform interference estimation, it may also result in that the demodulated first data stream is erroneous, and the interference estimation needs to be performed again.

On the other hand, the terminal device 116 may also receive interference from the neighboring cell, and an interference estimation needs to be performed on an interference channel of the neighboring cell, which further increases the complexity of the interference estimation.

In summary, if the terminal device 116 cannot know the transmission scheme and the DMRS port of the terminal device 122, complexity of interference estimation and data demodulation is greatly increased, which is a great challenge for the terminal device 116, and meanwhile, a time delay generated for data transmission is relatively large.

It should be understood that, in the above example, only 8 DMRS ports are taken as an example for illustration, but this should not limit the embodiments of the present invention at all, and for example, the number of DMRS ports may also be a greater number or a smaller number. And, it can be understood that the greater the number of DMRS ports, the higher the complexity of interference estimation and data demodulation that may be brought about.

In the above example, in the communication system of MU-MIMO, which is described only by taking interference estimation as an example, it is often beneficial for the terminal device if the receiving end device can know the transmission schemes and DMRS ports of other receiving end devices. Therefore, the present application provides a method for data transmission, which can predefine a corresponding relationship between a DMRS port and a transmission scheme, so that a receiving device can know DMRS ports and transmission schemes of other receiving devices in advance.

Hereinafter, a method for data transmission according to an embodiment of the present invention is described in detail with reference to fig. 3 to 7.

Fig. 3 is a schematic flow chart diagram of a method 300 for data transmission of an embodiment of the present invention, shown from the perspective of device interaction. It should be understood that fig. 3 shows communication steps or operations of a method for data transmission of an embodiment of the present invention, but these steps or operations are merely examples, and other operations or variations of the various operations in fig. 3 may also be performed by an embodiment of the present invention. Moreover, the various steps in FIG. 3 may be performed in a different order presented in FIG. 3, and it is possible that not all of the operations in FIG. 3 may be performed.

It should also be understood that, in the embodiments of the present invention, the "first" and the "second" are only used for distinguishing different objects, and should not constitute any limitation to the embodiments of the present invention. E.g., to distinguish between different terminal devices, different spatial streams, different demodulation reference signals, etc.

As shown in fig. 3, the method 300 includes:

s302, the network device obtains a first mapping relationship, where the first mapping relationship is used for a correspondence relationship between resources of multiple demodulation reference signals and at least one transmission scheme.

In the embodiment of the present invention, the first mapping relationship may be predefined by each network device and each terminal device, that is, may be statically configured. In this case, the first mapping relationship may be stored in advance in the memories of the network devices and the terminal devices, so that the network devices and the terminal devices may directly obtain the first mapping relationship from the memories when necessary. In other words, the correspondence between the port number of the demodulation reference signal and the transmission scheme is fixed and unchanged after the determination is made. For example, the first mapping relationship may be as shown in any one of fig. 4 to 8.

Alternatively, the first mapping relationship may also be determined according to the currently configured transmission scheme, i.e. may be dynamically configured or semi-statically configured.

Optionally, S302 specifically includes:

the network device determines a first mapping relation according to a predefined mapping rule and a resource of a demodulation reference signal required by a currently configured transmission scheme.

Specifically, the network device may select an appropriate mapping rule according to the demodulation reference signal resource required by the currently configured transmission scheme, and determine the first mapping relationship. The first mapping relationship may be used to indicate a correspondence relationship of resources of the plurality of demodulation reference signals to at least one transmission scheme. However, it should be understood that this does not mean that the number of demodulation reference signals has a one-to-one correspondence with the transmission scheme, and the number of demodulation reference signals has no direct relationship with the kind of the transmission scheme. When the network device transmits data to the terminal device, one or more demodulation reference signals may be configured for the same terminal device (for convenience of distinction and explanation, referred to as a first terminal device), and thus mapped to one transmission scheme. In other words, after mapping the data sent to the terminal device to one or more spatial layers, the network device may send the one or more spatial layers to the first terminal device, and correspondingly, the network device sends one or more demodulation reference signals to the terminal device.

For convenience of explanation, the first data stream is taken as an example in the embodiments of the present invention. It is understood that the first data stream is a spatial stream obtained after layer mapping, and may be one layer or a plurality of layers. In contrast, the first data stream after being precoded may become a first precoded data stream.

It should be noted that the first mapping relationship is only a predefined mapping relationship, or a pre-mapping rule. It is a rule followed by the network device when allocating the resources of the demodulation reference signal to the terminal device, but does not mean that all ports are configured to transmit data according to the corresponding transmission scheme. For example, when port #0 to port #7 in the first mapping relation are specified to correspond to transmission schemes of transmit diversity, which does not mean that all 8 ports of port #0 to port #7 are used for transmitting data using the transmission schemes of transmit diversity, the network device may use only one or more of the ports. That is, the network device needs to allocate the resource of the demodulation reference signal to the terminal device according to the first mapping relation according to the current need.

By way of example and not limitation, the resources of the demodulation reference signal may include at least one of: ports, scrambling codes, orthogonal codes, or orthogonal sequences. At least one of the resources of any two different demodulation reference signals is different. For example, different ports, different scrambling codes, or different scrambling codes for the same port, or different scrambling codes for different ports, or different orthogonal sequences, or different orthogonal codes for the same port, or different orthogonal sequences for the same port, etc.

The demodulation reference signals can be distinguished by the resources occupied by the demodulation reference signals in a certain dimension (e.g., a spatial domain or a code domain). Space division can be achieved by configuring different resources for demodulation reference signals in at least one dimension.

Wherein, the port number of the demodulation reference signal can indicate the orthogonal code and the time frequency resource.

The orthogonal codes used by the demodulation reference signals of different port numbers are different, or the time frequency resources are different, or the orthogonal codes and the time frequency resources are different.

For example, in downlink transmission, the network device usually distinguishes different demodulation reference signals by different port numbers, and also can distinguish different demodulation reference signals by different scrambling codes. In uplink transmission, different terminal devices may have the same port number, but may distinguish different demodulation reference signals by different orthogonal sequences. The demodulation reference signals are distinguished by scrambling codes or orthogonal masks. However, it should be understood that the above list is only an exemplary illustration, and should not constitute any limitation to the embodiments of the present invention, for example, the network device may also distinguish different demodulation reference signals by other resources besides the above list.

S304, the network device sends the first precoded data stream and the first precoded demodulation reference signal to the first terminal device.

Specifically, the first precoded demodulation reference signal is obtained by precoding a first demodulation reference signal, and the first precoded data stream is obtained by precoding the first data stream. The first demodulation reference signal corresponds to the first data stream, and the resource of the first demodulation reference signal corresponds to the transmission scheme of the first data stream, that is, the network device may determine the resource of the first demodulation reference signal according to a predetermined first mapping relationship and the transmission scheme of the first data stream, and transmit the first demodulation reference signal and the first data stream.

The network device may map the first precoded demodulation reference signal and the first precoded data stream to a same Resource Block (RB) and send the same to the first terminal device, where it can be understood that the REs occupied by the first precoded demodulation reference signal and the first precoded data stream are different.

The network device and the terminal device pre-store time-frequency resources, i.e., pilot patterns (patterns), occupied by demodulation reference signals at different ports, for example, the pilot patterns may be DMRS pilot patterns of the top 8 ports specified in a protocol, or DMRS pilot patterns of more or fewer ports specified in an existing or future protocol. After determining the port of the demodulation reference signal, the network device may determine the occupied time-frequency resource, i.e., RE, according to the pilot pattern, then map the data stream to the RE not occupied by the demodulation reference signal, and transmit the data stream through the antenna port after OFDM modulation. It should be understood that the specific method for determining the time-frequency resources occupied by the demodulation reference signals and the data according to the pilot pattern may be the same as the prior art, and a detailed description of the process is omitted here for brevity.

However, in most cases, the network device may transmit data with multiple terminal devices (including the first terminal device) in the same cell at the same time, and if one or more of the multiple terminal devices transmit data with the network device on the same time-frequency resource, the first terminal device may be interfered by other terminal devices; moreover, the first terminal device may also be located in a cell edge region, and if one or more terminal devices of the neighboring cell also transmit data on the same time-frequency resource, the first terminal device may also be interfered by the terminal device of the neighboring cell.

Hereinafter, for the sake of distinction and explanation, the terminal device that may interfere with the first terminal device described above will be referred to as a second terminal device. It can be understood that the second terminal device may be a terminal device located in the same cell as the first terminal device, or may be a terminal device in a neighboring cell, which is not particularly limited in this embodiment of the present invention. As long as the first terminal device and the second terminal device transmit data using the same time-frequency resource, interference from the second terminal device may occur, and interference estimation is required. In other words, the demodulation reference signal (referred to as the second demodulation reference signal for convenience of distinction and explanation) and the data stream (referred to as the second data stream for convenience of distinction and explanation) received by the second terminal device may be transmitted by the network device, or may be transmitted by other network devices. The embodiment of the present invention is not particularly limited thereto.

It is to be understood that the second terminal device may be one or more. And, the number of the second demodulation reference signals sent by the network device (for example, network device of the local cell or network device of the neighboring cell) to each second terminal device may also be one or more, and correspondingly, the number of the second data streams sent by the network device (for example, network device of the local cell or network device of the neighboring cell) to each second terminal device may be one layer or more. The embodiment of the present invention is not particularly limited thereto.

Here, for convenience of description only, it is assumed that the second terminal device is located in the same cell as the first terminal device, and the second terminal device receives the second data stream and the second demodulation reference signal transmitted by the same network device.

S306, the network device sends a second pre-coded demodulation reference signal and a second data stream, and the resource of the second pre-coded demodulation reference signal is determined according to the transmission scheme of the second data stream.

Specifically, the second precoded demodulation reference signal is obtained by precoding, by the network device, the second demodulation reference signal, and the second precoded data stream is obtained by precoding, by the network device, the second data stream. The second demodulation reference signal corresponds to a second data stream, and resources of the second demodulation reference signal correspond to a transmission scheme of the second data stream.

Before sending the second precoded demodulation reference signal to the second terminal device, the network device may determine the resource of the second demodulation reference signal according to the transmission scheme of the second data stream and the first mapping relationship, for example, the resource may be a port, a scrambling code, an orthogonal sequence, or the like of the second demodulation reference signal. In the embodiment of the present invention, the port of the second demodulation reference signal in downlink transmission is described.

The first terminal device does not know on which port the network device will send the second precoded demodulation reference signal and the second precoded data stream, but the first terminal device may attempt to receive the second precoded demodulation reference signal on each port. In case a second precoded demodulation reference signal is received, further interference estimation may be performed.

It can be understood that, if the second terminal device is a terminal device of the neighboring cell, the first terminal device may also receive, from a network device of the neighboring cell, the second precoded demodulation reference signal and the second precoded data stream that are sent to the second terminal device, which is not particularly limited in this embodiment of the present invention.

In S304 and S306, the first terminal device receives the first precoded demodulation reference signal and the first precoded data stream sent by the network device, and simultaneously monitors the second precoded demodulation reference signal and the second precoded data stream sent by the network device to other terminal devices.

Specifically, the first precoded demodulation reference signal is used to demodulate the first precoded data stream. That is, a channel matrix of the first precoded data stream is obtained through channel estimation, so that the first data stream is recovered. However, the first terminal device also receives the second precoded demodulation reference signal and the second precoded data stream at the same time, i.e. is interfered by other channels. Therefore, the first terminal device needs to estimate the interference channel to process the received signal to recover the first data stream.

S308, the first terminal device obtains the first mapping relation.

In this embodiment of the present invention, the first mapping relationship may be predefined, i.e., statically configured, for each network device and each terminal device (including the first terminal device). In this case, the first mapping relationship may be stored in advance in the memories of the network devices and the terminal devices, so that the network devices and the terminal devices may directly obtain the first mapping relationship from the memories when necessary. In other words, the correspondence between the port number of the demodulation reference signal and the transmission scheme is fixed and unchanged after the determination is made. By way of example and not limitation, the first mapping relationship may be as shown in any one of fig. 4-8.

Alternatively, the first mapping relationship may also be determined by the network device according to the resource of the demodulation reference signal required by the currently configured transmission scheme, that is, dynamically configured or semi-statically configured. In this case, the first mapping relationship is determined by the network device according to the mapping rule negotiated in advance with each terminal device (including the first terminal device) and the demodulation reference signal resource required by the currently configured transmission scheme, and the terminal device is notified of the indication information of the first mapping relationship through signaling. The first mapping relationship may also be specified by the network device and communicated to the first terminal device.

In a possible implementation manner, the network device directly sends the first mapping relationship to the first terminal device. In this case, the first terminal device does not need to determine the first mapping relationship by itself.

In another possible implementation manner, the network device and the first terminal device may pre-store a plurality of mapping relationships and indexes of the plurality of mapping relationships in a memory, where each of the plurality of mapping relationships corresponds to at least one transmission scheme, or each transmission scheme corresponds to at least one mapping relationship. After determining the first mapping relationship according to the demodulation reference signal resource required by the currently configured transmission scheme, the network device directly notifies the index of the first mapping relationship to the first terminal device, and the first terminal device can determine the first mapping relationship according to the index. In this implementation, the network device and the first terminal device do not need to determine various possible mapping relationships by themselves, and the network device only needs to determine an appropriate mapping relationship from the multiple mapping relationships according to the demodulation reference signal resource required by the currently configured transmission scheme, use the appropriate mapping relationship as the first mapping relationship, and send the indication information (i.e., the index) of the first mapping relationship to the first terminal device.

In another possible implementation manner, the network device and the first terminal device may determine at least one mapping relationship in advance according to at least one mapping rule negotiated by both parties (how to determine the mapping relationship according to the mapping rule will be described below with reference to the drawings), where each mapping relationship in the at least one mapping relationship is used to indicate resources of multiple demodulation reference signals and one possible transmission scheme of the at least one transmission scheme. Each mapping corresponds to an index. After determining the first mapping relationship according to the demodulation reference signal resource required by the currently configured transmission scheme, the network device directly notifies the index of the first mapping relationship to the first terminal device, and the first terminal device can determine the first mapping relationship according to the index. In this implementation, the first terminal device needs to determine various possible mapping relationships by itself. However, it can be understood that the first terminal device may store the first terminal device in the memory after determining the at least one mapping relationship according to the at least one mapping rule, and may directly determine the first mapping relationship according to the index when receiving the index of the first mapping relationship sent by the network device each time.

Specifically, the sending, by the network device, the indication information of the first mapping relationship to the first terminal device may be implemented in any one of the following three manners:

the first method is as follows: the network equipment sends a Radio Resource Control (RRC) message to the first terminal equipment, wherein the RRC message carries indication information of a first mapping relation; alternatively, the first and second electrodes may be,

the second method comprises the following steps: the network device sends a Media Access Control (MAC) control Cell (CE) to the first terminal device, wherein the MAC-CE carries the indication information of the first mapping relation; alternatively, the first and second electrodes may be,

the third method comprises the following steps: the network device sends a Physical Downlink Control Channel (PDCCH) to the first terminal device, where the PDCCH carries indication information of the first mapping relationship. Specifically, the indication information of the first mapping relationship is carried in DCI in the PDCCH.

The indication information of the first mapping relationship may be an index of a mapping rule corresponding to the first mapping relationship, or the indication information of the first mapping relationship may be the first mapping relationship itself.

If the first terminal device does not store the mapping rule and the index, the indication information of the first mapping relationship may be the first mapping relationship itself; if the first terminal device stores the plurality of mapping rules and the plurality of indexes, or stores the plurality of mapping relationships and the plurality of indexes, the first mapping relationship may be determined according to the indexes.

It should be noted that, if the second terminal device and the first terminal device do not belong to the same cell (for the convenience of differentiation and description, it is assumed that the first terminal device belongs to the first cell, the serving network device of the first cell is referred to as the first network device, the second terminal device belongs to the second cell, the serving network device of the second cell is referred to as the second network device), i.e. the serving network device of the second terminal device may be another network device and the first mapping relation is dynamically adjustable, when the network device is required to send to the first terminal device to indicate the first mapping relation currently used, the first network device may receive the indication information of the first mapping relationship from the second network device through an interface between the network devices (e.g., an X2 interface) and transmit the indication information of the first mapping relationship to the first terminal device. In this case, the first mapping relationship of the first cell and the first mapping relationship of the second cell may be different, and in order to distinguish the first mapping relationships of different cells, a cell identifier may be added to the indication information of the first mapping relationship, so that the first terminal device can distinguish the first mapping relationships of different cells.

It should be further understood that the above-listed method for the first terminal device to obtain the first mapping relationship is only an example, and should not constitute any limitation to the embodiment of the present invention, for example, the first terminal device may further perform subsequent processing according to the pre-stored first mapping relationship when the first mapping relationship sent by the network device is not received; and when the first mapping relation sent by the network equipment is received, carrying out subsequent processing according to the received first mapping relation.

The mapping rules are described in detail below with reference to the accompanying drawings.

Optionally, the mapping rule includes: according to the order from small to large of the index numbers of the resources of the demodulation reference signals, the index numbers of at least one demodulation reference signal are mapped to a transmission scheme in sequence from a certain index number.

In the embodiment of the present invention, optionally, the index number of the demodulation reference signal includes a port number of the demodulation reference signal.

As can be seen from the above mapping rule, no matter the transmission scheme configured by the network device for each terminal device includes one transmission scheme (case one) or multiple transmission schemes (case two), the port number corresponding to each transmission scheme may be relatively fixed.

It should be noted that any one transmission scheme may correspond to at least one mapping relationship, for example, the transmission scheme may be: space Frequency Block Code (SFBC), pre-coded polling or CLSM, etc. The first mapping relationship described below with reference to the drawings is only an exemplary illustration and should not be construed as limiting the embodiments of the present invention.

The first condition is as follows:

the mapping rule includes: when the transmission schemes configured by the network device for the terminal devices only include one transmission scheme, at least one demodulation reference signal port is mapped to one transmission scheme in sequence according to the sequence of port numbers from small to large. In this case, the specific port number is port # 0.

Assuming that the communication system supports data transmission of 8 ports at most, the network device transmits data with different terminal devices by using the same transmission scheme. For example, the same transmission scheme is SFBC. One or more ports can be mapped to one transmission scheme from port #0 to port #7 in the order of port numbers from small to large, respectively, according to the above mapping rule. Typically, the number of ports required for SFBC is an even number, and may be, for example, 2, 4 or more. According to the required port number, from port #0, the ports are mapped to the same transmission scheme in sequence, that is, data is transmitted to one terminal device by adopting SFBC.

Typically, at least one port number in succession may be mapped to a transmission scheme, directed to a terminal device.

Fig. 4 is a schematic diagram illustrating a correspondence relationship between port numbers of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention. As shown in fig. 4, if 2 ports are needed, in case of a port completely unoccupied, two ports are mapped to a transmission scheme in sequence starting from port #0 for transmitting data to a terminal device. For example, port #0 and port #1 point to terminal device #1, port #2 and port #3 point to terminal device #2, port #4 and port #5 point to terminal device #3, and port #6 and port #7 point to terminal device # 4; if 4 ports are needed, in case of a completely unoccupied port, starting from port #0, four ports are mapped to a transmission scheme in sequence for transmitting data to a terminal device. If more ports are needed, according to the same method, according to the sequence of the port numbers from small to large, a plurality of ports can be mapped to a transmission scheme in sequence and point to a terminal device.

It should be understood that the SFBC is taken as one possible transmission scheme to exemplarily illustrate the mapping rule, and should not constitute any limitation to the embodiment of the present invention. For example, the transmission scheme may also be CLSM, precoding polling, etc.

When the transmission scheme only needs to pass through one demodulation reference signal port, for example, the CLSM may map each port to one transmission scheme in turn according to the sequence of port numbers from small to large, and point to one terminal device.

Or, when the transmission scheme requires three demodulation reference signal ports, according to the mapping rule, each three ports may be sequentially mapped to one transmission scheme according to the sequence of port numbers from small to large, and the transmission scheme is directed to one terminal device.

In this case, the mapping rule may also be defined as: a plurality of ports in series are mapped to one transmission scheme, starting with a port having an even number as a first port. Then the specific port number is port #0 for the pre-coded polling case described above. Port #0, port #1, and port #2 are mapped to one transmission scheme and directed to one terminal device, and port #4, port #5, and port6 are mapped to one transmission scheme and directed to another terminal device.

Further alternatively, the mapping rule may be defined as: if a plurality of consecutive ports are mapped to one transmission scheme starting from the port with the odd number of ports as the first port, the specific port number is port #1 for the case of the above-described pre-coded polling. For the sake of brevity, this is not listed here.

It should be understood that the number of demodulation reference signal ports required by the various transmission schemes listed above is merely an exemplary illustration, and should not constitute any limitation on the embodiments of the present invention. The network device may determine the mapping relationship according to the number of demodulation reference signal ports that may be required for various transmission schemes specified in existing or future protocols.

Case two:

the mapping rule includes: under the condition that the transmission schemes configured by the network equipment for each terminal equipment include at least two transmission schemes, dividing a plurality of demodulation reference signal ports into at least two groups, wherein the port numbers of each group of demodulation reference signal ports are continuous, each group of demodulation reference signal ports corresponds to one transmission scheme, and mapping at least one demodulation reference signal port to one transmission scheme in sequence according to the sequence of the port numbers from small to large.

Assuming that the communication system supports data transmission of 12 ports at most, which are port #0 to port #11, the network device transmits data with different terminal devices using two transmission schemes. For example, the two transmission schemes are SFBC and precoded polling. The 12 ports can be divided into two groups according to the above mapping rule, and the port numbers of each group of ports are consecutive.

Further, the mapping rule may further specify a first port number mapped to each transmission scheme.

The network device may determine the first mapping relationship according to a port of the demodulation reference signal required by the currently configured transmission scheme and a predefined mapping rule.

For example, according to rule one: port #0 is taken as the first port number mapped to SFBC and port #6 is taken as the first port number mapped to precoded polls. That is, the first 6 port numbers are grouped and mapped to SFBC, and the last 6 port numbers are grouped and mapped to precoded polling, as shown in fig. 5. Fig. 5 is another schematic diagram of correspondence between port numbers of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention.

Or, according to rule two: port #0 is taken as the first port number mapped to precoded polls and port #6 is taken as the first port number mapped to SFBC. That is, the first 6 port numbers are grouped and mapped to the pre-coded poll, and the last 6 port numbers are grouped and mapped to the SFBC.

Or, according to rule three: port #0 is taken as the first port number mapped to SFBC and port #4 is taken as the first port number mapped to precoded polls. That is, the first 4 port numbers are grouped and mapped to SFBC, and the last 8 port numbers are grouped and mapped to precoded polling.

Or, according to rule four: port #0 is taken as the first port number mapped to the precoded poll and port #4 is taken as the first port number mapped to the SFBC. That is, the first 4 port numbers are grouped and mapped to pre-coded polling, and the last 8 port numbers are grouped and mapped to SFBC.

By analogy, for the sake of brevity, one is not listed again. Thereby, the first terminal device can obtain a plurality of mapping relationships corresponding to the plurality of mapping rules.

It should be understood that the above exemplary SFBC and precoding polling are exemplary illustrations of mapping rules as possible transmission schemes, and should not constitute any limitation to the embodiments of the present invention. For example, the at least one transmission scheme may also include other transmission schemes, such as CLSM.

Further, when the at least one transmission scheme includes two or more transmission schemes and the number of ports required by the two or more transmission schemes is different, the following mapping rule may be followed.

It is assumed that the communication system supports data transmission of a maximum of 8 ports, port #0 to port #7, respectively, and the network device transmits data with different terminal devices using two transmission schemes. For example, the two transmission modes include SFBC and CLSM.

If each terminal device under the SFBC transmission scheme needs 2 ports, and each terminal device under the CLSM transmission scheme needs 1 port. The mapping of the 8 ports still follows the above mapping rule, and the 8 ports are divided into two groups, one for each transmission scheme. Each transmission scheme is mapped in sequence from a specific port number according to the sequence of the port numbers from small to large. For example, port #0 is used as the first port number mapped to SFBC, and port #3 is used as the first port number mapped to CLSM, that is, the first 4 port numbers are grouped and mapped to SFBC, and each two port numbers point to one terminal device; the last 4 port numbers are grouped and mapped to CLSM, each port number pointing to a terminal device, as shown in fig. 6. Fig. 6 is another schematic diagram of correspondence between port numbers of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention.

It should be understood that the above lists defined mapping relationships according to various mapping rules, but this should not limit the embodiments of the present invention in any way. In addition, it should be noted that, after the communication system determines the above multiple mapping rules, the network device and the terminal device define the same index or identifier for each mapping rule, so as to distinguish different mapping relationships.

It should be further noted that the first mapping relationship may be determined by the network device and the terminal device according to at least one mapping rule negotiated in advance, and may be applicable to the entire communication system. The network device and the terminal device in the cell where the first terminal device is located and the neighboring cells all follow the at least one mapping rule to determine the correspondence between the resource of the demodulation reference signal and the transmission scheme. Although the first mapping relationship followed by the two cells at a certain time may be different, the first mapping relationship is determined according to one of the at least one mapping rule, and it can be understood that both the terminal device and the network device can obtain the first mapping relationship of the local cell or the neighboring cell.

Through the above description, the first terminal device obtains the first mapping relationship.

It should be noted that in S302, the network device may determine the first mapping relationship according to the resource of the demodulation reference signal required by the currently configured transmission scheme. Still taking the port as an example, if the network device determines that all currently configured transmission schemes are SFBC, the mapping rule described above with reference to fig. 4 may be directly selected to determine the first mapping relationship; if the network device determines that the currently configured transmission scheme uses more ports for SFBC and fewer ports for pre-coding polling, the mapping rule described above with reference to fig. 5 may be selected to determine the first mapping relationship.

It should be understood that the above describes the mapping rule in detail only by taking a port number as an example, but this should not limit the embodiment of the present invention at all, for example, the first mapping relationship may also be a corresponding relationship between index numbers of scrambling code identifiers of a plurality of demodulation reference signals and at least one transmission scheme, or a corresponding relationship between port numbers of a plurality of demodulation reference signals, index numbers of scrambling code identifiers and at least one transmission scheme. As shown in fig. 7 and 8. Fig. 7 is a schematic diagram of a correspondence relationship between indexes of scrambling code identifiers of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention. Fig. 8 is a schematic diagram illustrating a correspondence relationship between port numbers of multiple demodulation reference signals, index numbers of scrambling code identifiers, and at least one transmission scheme according to an embodiment of the present invention. It can be seen that, in the case of resource determination of the demodulation reference signal, the transmission scheme of the corresponding data stream may also be determined. It should be further understood that fig. 7 and fig. 8 are only the corresponding relationship between the resource of the demodulation reference signal and the transmission scheme, which is shown for facilitating understanding, and should not constitute any limitation to the embodiments of the present invention.

It should be particularly noted that, in a specific implementation process, resources of corresponding demodulation reference signals may be set for each transmission scheme, or may be set for only a part of the transmission schemes.

For example, when the transmission schemes include SFBC, precoding polling, and CLSM, resources of corresponding demodulation reference signals may be set for each transmission scheme, or corresponding demodulation reference signals may be set for only two transmission schemes, namely SFBC and precoding polling, without setting corresponding demodulation reference signals for CLSM.

In this case, the network device may preferentially configure resources of demodulation reference signals for both transmission schemes of SFBC and precoded polling, and then configure resources of demodulation reference signals for CLSM. That is, SFBC and precoding polling are directly associated with the resources of the demodulation reference signals, while CLSM is indirectly associated with the resources of the demodulation reference signals.

Although the first terminal device cannot accurately determine the transmission schemes of the data streams corresponding to none of the demodulation reference signals directly according to the first mapping relationship, compared with a method of trying different transmission schemes on all unused ports in a traversal manner in the prior art, the blind detection range is reduced, the complexity of interference estimation and demodulation of the receiving terminal device is reduced to a certain extent, and the time delay brought by data processing is reduced.

For example, assuming that the communication system supports data transmission of up to 12 ports, the network device determining the currently configured transmission scheme includes: SFBC, CLSM and precode polling, the network device may map the transmission schemes of SFBC and precode polling onto the ports according to the mapping rule according to the predefined mapping rule, as shown in fig. 5. However, when the network device allocates the port of the demodulation reference signal to the terminal device, only port #0 and port #1, port #2 and port #3, and port #6 and port #7 may be used, and the network device may further allocate the unoccupied ports (i.e., port #4 and port #5, and port #8 to port #11) to the transmission scheme of the CLSM. The network device may allocate any one or more of the remaining 6 ports to the CLSM, or may allocate ports to the terminal devices of the CLSM according to a predefined mapping rule. This is not particularly limited in the present application.

S310, the first terminal device determines the resource of the first demodulation reference signal and the transmission scheme of the first data stream.

Optionally, the DCI sent by the network device to the first terminal device carries indication information of the resource of the first demodulation reference signal.

The first terminal device may determine, directly according to the indication field in the DCI, a port number of the first demodulation reference signal and/or an index number (n) of a scrambling identity (scrambling identity)_SCID)。

Optionally, the DCI sent by the network device to the first terminal device carries indication information of the transmission scheme of the first data stream.

The first terminal device may determine the transmission scheme of the first data stream directly according to the DCI sent by the network device. In this case, the DCI carries the indication information of the transmission scheme, which may be implemented by adding an indication field in the DCI or indicating the indication by using an existing reserved field.

Alternatively, the first terminal device may also determine the transmission scheme of the first data stream according to the port of the first precoding demodulation reference signal according to the first mapping relationship obtained in S310.

S312, the first terminal device demodulates the first precoded data stream according to the first precoded demodulation reference signal.

The first terminal device estimates an equivalent channel matrix of the first precoded data stream according to the first precoded demodulation reference signal received in S308, and further demodulates the first precoded data stream.

However, since the first terminal device receives the first precoded data stream and also receives the second precoded data stream and the second precoded demodulation reference signal that are sent to other devices by the network device, which may generate interference back to the first precoded data stream, resulting in that the first data stream cannot be recovered, the first terminal device needs to perform interference estimation.

S314, the first terminal device may determine the transmission scheme of the second data stream according to the association relationship between the resource of the demodulation reference signal and the transmission scheme and the resource of the second demodulation reference signal.

In the embodiment of the present invention, the association relationship between the resource of the demodulation reference signal and the transmission scheme may be a direct association relationship, for example, a correspondence relationship between the resources of the plurality of demodulation reference signals and at least one transmission scheme, that is, a first mapping relationship.

Specifically, the first terminal device may determine, according to the port corresponding to the received second demodulation reference signal and the first mapping relationship, that the transmission scheme corresponding to the port of the second demodulation reference signal is the transmission scheme of the second data stream.

For example, assume that the first mapping relationship currently used is as shown in fig. 4. If the first terminal device receives the first precoded demodulation reference signals at port #2 and port #3, the first terminal device may determine that port #0 and port #1 are already occupied and also use the transmission scheme of SFBC, and the following 4 ports (port #4 to port #7) are not occupied, the first terminal device may determine that the second precoded demodulation reference signals correspond to port #0 and port #1, directly receive the second precoded demodulation reference signals at port #0 and port #1, and determine that the transmission schemes of the two ports are SFBC. Therefore, the first terminal device does not need to try other transmission schemes on port #0 and port #1, and can estimate the channel matrix of the interference channel directly according to the transmission scheme of SFBC. Thereafter, the first terminal device continues to attempt to receive the second precoded demodulation reference signals on port #4 to port #7, and estimates a channel matrix of the interference channel from the SFBC and the received demodulation reference signals in case of reception.

If the first terminal device receives the first precoded demodulation reference signals at port #4 and port #5, the first terminal device may determine that port #0 to port #3 are already occupied, and also use the SFBC transmission scheme. The second precoded demodulation reference signal may correspond to 4 ports, i.e., port #0 to port #3, or the second precoded demodulation reference signal is a demodulation reference signal for two terminal devices, i.e., the number of the second terminal devices is 2, each second terminal device corresponds to 2 ports, i.e., two groups of ports, i.e., port #0, port #1, and port #2, port #3, and the first terminal device may try to receive the second precoded demodulation reference signal on the two groups of ports, respectively, and further estimate the channel matrix of the interference channel according to the transmission scheme of SFBC when receiving the second precoded demodulation reference signal. Thereafter, the first terminal device continues to attempt to receive the second precoded demodulation reference signals on port #6 and port #7, and estimates a channel matrix of the interference channel from the SFBC and the received demodulation reference signals in case of reception.

For another example, assume that the first mapping relationship currently used is as shown in fig. 5. If the first terminal device receives the first precoded demodulation reference signals at port #2 and port #3, the first terminal device may determine that port #0 and port #1 are already occupied, and also use the SFBC transmission scheme; however, the first terminal device does not determine whether the last 8 ports (port #4 to port #11) are used, but it can be determined that if the second precoded demodulation reference signals are received on port #4 and port #5, the SFBC transmission scheme is still used on port #4 and port # 5. If one of the last 6 ports (port #6 to port #11) is used, it must be port #6, and the corresponding transmission scheme is pre-coded polling. The first terminal device may attempt to receive the second precoded demodulation reference signal from port #6, and if the second precoded demodulation reference signal is not received, it indicates that all the last 6 ports are unoccupied, and if the second precoded demodulation reference signal is received, the second precoded demodulation reference signal may be further received on port #7, and a channel matrix of the interference channel may be estimated according to a transmission scheme of precoded polling. Until the second precoded demodulation reference signal is not received on a certain port (e.g., port #10), which means that the ports following the port (i.e., port #10 and port #11) are both unoccupied, no further attempt to receive the second precoded demodulation reference signal is needed.

For another example, assume that the first mapping relationship currently used is as shown in fig. 6. If the first terminal device receives the first precoding demodulation reference signal on port #7, the first terminal device may determine that ports #4 to port #7 are occupied and all use the transmission scheme of the CLSM; however, the first terminal device does not determine whether the first 4 ports (port #0 to port #3) are used, but it can be determined that if one of the first 4 ports is used, it is necessarily port #0, and the corresponding transmission scheme is SFBC. The first terminal device may attempt to receive a second precoded demodulation reference signal from port #0, if the second precoded demodulation reference signal is not received, it indicates that all the first 4 ports are unoccupied, and if the second precoded demodulation reference signal is received, the first terminal device may further receive the second precoded demodulation reference signal on port #1, and estimate a channel matrix of an interference channel according to a transmission scheme of SFBC. Until the second precoding demodulation reference signal is not received at a port (port #2), it indicates that the ports after the port change (i.e., port #2 to port #3) are all unoccupied, and no attempt is made to receive the second precoding demodulation reference signal.

As can be seen from the above example, compared to the method of traversing and trying different transmission schemes on all unused ports in the prior art, the embodiment of the present invention reduces the range of guessing (or blind detection) by the first terminal device, and reduces the complexity of interference estimation and demodulation.

It should be noted that, the above-described first terminal device determines, according to the first mapping relationship and the resource of the second demodulation reference signal, that the transmission scheme of the second data stream has a direct association relationship, the association relationship between the resource of the demodulation reference signal and the transmission scheme may also be indirect, and the first mapping relationship may be determined only according to a part of the transmission scheme and a predefined corresponding mapping rule, so that the first terminal device may still determine the transmission scheme of the second data stream according to the first mapping relationship and the resource of the second demodulation reference signal.

For example, assume that the first mapping relationship is as shown in fig. 4, and the network device uses two transmission schemes, SFBC and CLSM. Fig. 4 only defines the correspondence between SFBC and the port number of the demodulation reference signal, that is, the network device preferentially allocates a port to SFBC and allocates the remaining unoccupied ports to CLSM.

For example, if a first terminal device receives first precoded demodulation reference signals at port #4 and port #5, and the transmission scheme of a first data stream corresponding to the first precoded demodulation reference signals is SFBC, the first terminal device may determine that port #0 and port #1, port #2 and port #3 are also used, and only need to try various transmission schemes (e.g., SFBC, precoded polling, CLSM, etc.) at port #6 and port #7 for interference estimation and data demodulation corresponding to SFBC. Compared with the method of traversing and trying different transmission schemes on all unused ports adopted in the prior art, the method and the device for estimating the interference reduce the range of guessing (or blind detection) by the first terminal device and reduce the complexity of interference estimation and demodulation.

Assume that the first mapping relationship is as shown in fig. 5, and the network device uses three transmission schemes of SFBC, pre-coding polling and CLSM. Only the correspondence between SFBC and pre-coded polling and the port number of the demodulation reference signal is defined in fig. 5, that is, the network device preferentially allocates the ports to both the SFBC and pre-coded polling transmission schemes, and allocates the remaining unoccupied ports to the CLSM.

For example, if a first terminal device receives first precoded demodulation reference signals at port #4 and port #5, and the transmission scheme of a first data stream corresponding to the first precoded demodulation reference signals is SFBC, it may be determined that the network device allocates 6 ports of port #0 to port #5 to the SFBC, and the first terminal device may determine that port #0 and port #1, and port #2 and port #3 are also used and correspond to the SFBC. The first terminal device continuously tries to receive a second precoding reference signal on port #6, and if the second precoding reference signal is received on port #6, the first terminal device preferentially tries precoding polling on port #6 for interference estimation and demodulation; if the second precoding reference signal is not received at port #6, it indicates that the transmission schemes of port #6 to port #11 do not use precoding polling, and it is possible to attempt interference estimation and data demodulation at port #6 to port #11 using transmission schemes other than precoding polling (e.g., CLSM, SFBC, etc.). Compared with the method of traversing and trying different transmission schemes on all unused ports adopted in the prior art, the method and the device for estimating the interference reduce the range of guessing (or blind detection) by the first terminal device and reduce the complexity of interference estimation and demodulation.

S314, the first terminal device determines a channel matrix of an interference channel according to the transmission scheme of the second data stream and the second demodulation reference signal.

As already explained above, in some transmission schemes (e.g., precoded polling), the channel matrix of the entire RB is estimated to be inaccurate based on the precoding vector of one demodulation reference signal; alternatively, the use of the channel matrix of the interfering channel estimated by the precoding vector of the demodulation reference signal in some transmission schemes (e.g., SFBC) is inaccurate. Therefore, the first terminal device needs to estimate the channel matrix of each RE more accurately according to the transmission scheme of the second data stream and the port of the second demodulation reference signal, or use the channel matrix of the interference channel more accurately.

For example, in the case of the SFBC transmission scheme, assuming that two spatial streams are obtained by preprocessing one original spatial stream with transmit diversity, the network device transmits two data streams (i.e., the second data stream) corresponding to the two spatial streams using two demodulation reference signal ports. For example, the transmission signal S of the second data stream may be:

wherein s denotes the conjugate of s.

If the transmission scheme is unknown, the channel matrixes estimated according to the two received demodulation reference signals are respectively: h is₁And h₂If it is directly according to h₁And h₂Determining the covariance matrix of the interfering channel, the use of the channel matrix is inaccurate.

Since the transmission scheme is SFBC, assuming that the second precoded data stream corresponds to two layers, the channel matrix estimated according to the received second precoded demodulation reference signals (it can be understood that the number of the demodulation reference signals corresponding to the second precoded data stream is 2) should be the channel matrix estimated according to the received second precoded demodulation reference signals

According to the channel matrix, the covariance matrix of the interference channel can be determined, and then the received signal is processed.

For another example, in the case that the transmission scheme is precoded polling, fig. 9 shows a schematic diagram of precoding different REs in the same RB. It can be seen that, on one OFDM symbol, REs corresponding to multiple (e.g., 4) consecutive subcarriers are grouped, and precoding vectors of REs in each group are different two by two. In other words, when the transmission scheme of precoding polling is adopted, the granularity of precoding is RE, i.e., RE-level (RE-level), which is different from other transmission schemes. For example, the precoding granularity of SFBC is RB, i.e., RB level (RB-level). When each RE is processed, the used demodulation reference signals are different, the corresponding precoding vectors are different, the estimated channel matrixes of the interference channels are different, and the obtained covariance matrixes of the interference channels are also different.

S316, the first terminal device determines an interference noise covariance matrix according to the channel matrix of the interference channel.

Specifically, the first terminal may estimate a channel matrix of a corresponding interference channel according to the received at least one second precoded demodulation reference signal, and further obtain an interference noise covariance matrix.

For example, for the ith interfering channel, assume the channel matrix is H_iThen the corresponding interference noise covariance matrix is H_iH_i ^H. It can be appreciated that the resulting interference noise covariance matrix is different for different channel matrices. For example, for the transmission scheme of SFBC, if the channel matrix is

The corresponding interference noise covariance matrix is

Wherein H represents a conjugate transpose; for another example, for a transmission scheme of precoding polling, the channel matrices corresponding to any two REs in the same group are different, and the corresponding interference noise covariance matrices are also different, and when processing signals on each RE, it is necessary to determine the interference noise covariance matrix according to the channel matrix used by each RE.

S318, the first terminal device processes the received signal according to the interference noise covariance matrix to recover the first data stream.

The first terminal device may process the received signal according to the following formula:

where i denotes the channel of the first data stream, j denotes the interference channel, N₀I represents highWhite noise, W represents the weight matrix.

Further according to the formula Y ═ Hx + N₀Can obtain

Wherein the content of the first and second substances,

representing a signal received by the first terminal device;

a vector representing a first data stream transmitted by a network device;

representing white gaussian noise; h represents a channel matrix;

an estimate of a vector representing a first data stream transmitted by a network device.

Through the above processing, the first terminal device can recover the first data stream. The first terminal device checks according to a Cyclic Redundancy Check (CRC) code in the first data stream, and if the check is successful, it indicates that the demodulation of the first data stream is successful; if the verification is unsuccessful, interference estimation needs to be performed again.

It should be understood that the MMSE-IRC algorithm for processing the received signal and the data demodulation process of the above examples may be the same as those of the prior art, and a detailed description of the specific process thereof is omitted here for brevity.

It should also be understood that MMSE-IRC as a receiving algorithm using an interference noise covariance matrix is only an exemplary illustration, and should not constitute any limitation to the embodiment of the present invention, and the embodiment of the present invention may also recover the data stream by other methods for processing the interference signal.

It should also be understood that the above-listed method for determining the transmission scheme of the interfering data stream according to the first mapping relationship and the resources of the demodulation reference signal is only an exemplary illustration, and the present application does not exclude the possibility of notifying the target receiving end device of the resources used by the interfering device in the existing or future protocol, in which case the method of the embodiment of the present invention is also applicable.

Therefore, in the embodiment of the present invention, by defining the correspondence between the resources of the demodulation reference signal and at least one transmission scheme in advance, and allocating the resources of the demodulation reference signal to different transmission schemes according to the correspondence, when receiving the interference signal, the receiving end device can directly determine the transmission scheme used by the interference signal according to the correspondence, or blindly detect the transmission scheme used by the interference signal in a smaller range, so as to process the signal. The complexity of interference estimation and demodulation of receiving end equipment is reduced to a certain extent, and the time delay brought by data processing is reduced.

The method 300 for data transmission in downlink transmission is described in detail above with reference to fig. 3 to 9. It will be appreciated that the method is equally applicable to uplink transmissions. The method 400 for data transmission in uplink transmission is described in detail below with reference to fig. 10 to 13.

Specifically, in uplink transmission, a sending end device is a terminal device, a receiving end device is a network device, and two or more terminal devices may respectively send data to two or more network devices. Fig. 10 shows a schematic diagram of a communication system suitable for use in the method for data transmission of an embodiment of the invention. As shown in fig. 10, terminal apparatus #1 transmits data to network apparatus #1 on time-frequency resource # a, terminal apparatus #2 transmits data to network apparatus #2 on the same time-frequency resource (i.e., time-frequency resource # a), and network apparatus #1 and network apparatus #2 are base stations of two adjacent cells, so that network apparatus #1 may be interfered by pilot and data transmitted by terminal apparatus #2 to network apparatus #2 while receiving data transmitted by terminal apparatus # 1. The solid line in the figure shows the data transmitted by the terminal device to the network device, and the dotted line shows the interference caused by the data transmitted by another terminal device to the network device.

It should be noted that, in general, port numbers used by different terminal devices may be repeated, and demodulation reference signals of different terminal devices may be distinguished by different orthogonal sequences, that is, resources of the demodulation reference signals include orthogonal sequences or orthogonal codes of the demodulation reference signals. By using different orthogonal codes or orthogonal sequences for scrambling, different terminal devices can transmit data on the same time-frequency resource. The orthogonal sequence and the orthogonal sequence can be distinguished by the index number of the orthogonal sequence, and the orthogonal code can be distinguished by the index number of the orthogonal code. Therefore, in the embodiment of the present invention, the resource of the demodulation reference signal includes an orthogonal sequence or an orthogonal code.

Fig. 11 is a schematic flow chart diagram of a method 400 for data transmission provided by another embodiment of the present invention, shown from the perspective of device interaction. It should be understood that fig. 11 shows communication steps or operations of a method for data transmission of an embodiment of the present invention, but these steps or operations are merely examples, and other operations or variations of the various operations in fig. 11 may also be performed by an embodiment of the present invention. Moreover, the various steps in FIG. 11 may be performed in a different order presented in FIG. 11, and it is possible that not all of the operations in FIG. 11 may be performed.

It should also be understood that, in the embodiments of the present invention, the "first" and the "second" are only used for distinguishing different objects, and should not constitute any limitation to the embodiments of the present invention. E.g., to distinguish between different cells, different network devices, different terminal devices, different spatial streams, different demodulation reference signals, etc.

In the embodiment illustrated by method 400, it is assumed that a first network device (e.g., which may correspond to network device #1 in fig. 11) and a first terminal device (e.g., which may correspond to terminal device #1 in fig. 11) are devices of a first cell, and a second network device (e.g., which may correspond to network device #2 in fig. 11) and a second terminal device (e.g., which may correspond to terminal device #2 in fig. 11) are devices of a second cell.

As shown in fig. 11, the method 400 includes:

s402, the first network equipment acquires a first mapping relation of the first cell.

The first mapping relation of the first cell is used for indicating the corresponding relation between the resources of the plurality of demodulation reference signals and at least one transmission scheme in the first cell.

As described in S302, the first mapping relationship may be statically configured, that is, the first mapping relationship may be predefined by each network device and each terminal device and stored in the memory of each network device and each terminal device, so that the network device and the terminal device can directly obtain the mapping relationship from the memory when necessary. In this case, the first mapping relationships between the cells may be the same or different, and in different cases, the network device of each cell may store the first mapping relationship of each cell and the first mapping relationship of the neighboring cell in advance.

Alternatively, the first mapping relationship may be a dynamic or semi-static configuration. The first mapping relationship of the first cell may be determined by the first network device according to a predefined mapping rule and resources of demodulation reference signals required by the currently configured transmission scheme. In this case, the first mapping relationship may be different for each cell.

S404, the first terminal device obtains a first mapping relationship of the first cell.

If the first mapping relation is static configuration, the first terminal device can directly obtain the first mapping relation from a memory; if the first mapping relationship is configured dynamically or semi-statically, the first network device may notify the first terminal device in a broadcast manner.

S406, the second network device obtains the first mapping relationship of the second cell.

S408, the second terminal device obtains the first mapping relation of the second cell.

It should be understood that the specific process of S406 is the same as the specific process of S402, and the specific process of S408 is the same as the specific process of S404, and therefore, for brevity, the detailed description is omitted here.

It should be noted that, in uplink transmission, since the port numbers of the terminal devices may be the same, demodulation reference signals sent by different terminal devices cannot be distinguished, and demodulation reference signals sent by different terminal devices may be distinguished through orthogonal sequences. In this case, the first mapping relationship may be used to indicate a correspondence relationship between the index numbers of the orthogonal sequences of the plurality of demodulation reference signals and at least one transmission scheme, as shown in fig. 12. Alternatively, the first mapping relationship may also be used to indicate a port of the demodulation reference signal, a correspondence relationship between an index number of the orthogonal sequence and at least one transmission scheme, as shown in fig. 13.

For convenience of explanation, it is assumed herein that the first mapping relationship is the same from cell to cell.

Fig. 12 is a schematic diagram illustrating a correspondence relationship between index numbers of orthogonal sequences of multiple demodulation reference signals and at least one transmission scheme according to an embodiment of the present invention. Fig. 12 shows the correspondence between the index numbers of the eight orthogonal sequences and at least one transmission scheme, and regardless of the number of terminal devices, if the number of index numbers of the provided orthogonal sequences is determined, resources for demodulating reference signals can be allocated for the transmission scheme according to the first mapping relation as shown in fig. 12.

Fig. 13 is a schematic diagram illustrating a correspondence relationship between port numbers of multiple demodulation reference signals, index numbers of orthogonal sequences, and at least one transmission scheme according to an embodiment of the present invention. Assuming that each terminal device provides two ports at most, fig. 13 shows the correspondence of eight port numbers of four terminal devices, index numbers of eight orthogonal sequences, and at least one transmission scheme. It can be seen that the orthogonal sequences of any two ports are different, and even if the port numbers are the same, the demodulation reference signals of different terminal devices can be distinguished by different orthogonal sequences.

S410, the first terminal device sends a first pre-coding demodulation reference signal and a first pre-coding data stream to the first network device.

The first precoded demodulation reference signal is obtained by precoding the first demodulation reference signal, and the first precoded data stream is obtained by precoding the first data stream. The first demodulation reference signal corresponds to the first data stream, and the resource of the first demodulation reference signal corresponds to the transmission scheme of the first data stream, that is, the first terminal device may determine the orthogonal sequence of the first demodulation reference signal according to a predetermined first mapping relationship of the first cell and the transmission scheme of the first data stream, perform scrambling processing on the first demodulation reference signal, and then transmit the first demodulation reference signal and the first data stream.

S412, the second terminal device sends the second precoded demodulation reference signal and the second precoded data stream to the second network device.

The second precoded demodulation reference signal is obtained by precoding the second demodulation reference signal, and the second precoded data stream is obtained by precoding the second data stream. The second demodulation reference signal corresponds to the second data stream, and the resource of the second demodulation reference signal corresponds to the transmission scheme of the second data stream, that is, the second terminal device may determine the orthogonal sequence of the second demodulation reference signal according to the predetermined second mapping relationship of the second cell and the transmission scheme of the second data stream, perform scrambling processing on the second demodulation reference signal, and send the second demodulation reference signal and the second data stream.

In S410 and S412, the first network device receives the first precoded demodulation reference signal and the first precoded data stream transmitted by the first terminal device, and the second precoded demodulation reference signal and the second precoded data stream transmitted by the second terminal device.

That is, the first network device may be interfered by the second precoded demodulation reference signal and the second precoded data stream when receiving the first precoded demodulation reference signal and the first precoded data stream.

S414, the first network device determines a transmission scheme of the first data stream according to the first mapping relationship of the first cell.

The specific process of S414 may be the same as the specific process of S310, and for brevity, will not be described again here.

S416, the first network device obtains the first mapping relationship of the second cell.

If the first mapping relationship is configured statically, the first mapping relationship of the second cell and the first mapping relationship of the first cell may be the same or different. Under the condition that the first mapping relationship of the first cell is the same as the first mapping relationship of the second cell, the first network device may directly use the first mapping relationship of the first cell as a common first mapping relationship of each cell; when the first mapping relationship of the first cell and the first mapping relationship of the second cell are different, the first terminal device may obtain the first mapping relationship of the second cell from the first network device in advance, and store the first mapping relationship in the memory, or the first terminal device may send the first mapping relationship of the second cell to the first terminal device in a broadcast manner.

If the first mapping relationship is configured dynamically or semi-statically, the second network device may send the first mapping relationship of the second cell to the first network device through an interface between network devices (e.g., an X2 interface), and the first network device may send the first mapping relationship of the second cell to the first terminal device in a broadcast manner.

S418, the first network device determines a transmission scheme of the second data stream according to the first mapping relationship of the second cell and the resource of the received second precoding demodulation reference signal.

The first network device may determine, according to the first mapping relationship of the second cell, a transmission scheme corresponding to the received orthogonal sequence of the second precoding demodulation reference signal, that is, a transmission scheme of the second data stream.

S420, the first network device determines a channel matrix of the interference channel according to the transmission scheme of the second data stream and the second precoded demodulation reference signal.

S422, the first network device determines an interference noise covariance matrix according to the channel matrix of the interference channel.

S424, the first network device processes the received signal to recover the first data stream.

It should be understood that the specific processes of S418 to S424 may be the same as or similar to the specific processes of S312 to S318, and therefore, for brevity, the detailed description thereof is omitted.

It should be understood that the above listed resources of the demodulation reference signals are only examples, and should not constitute any limitation to the embodiments of the present invention, for example, in the downlink transmission, it is also possible to distinguish different demodulation reference signals by orthogonal codes, orthogonal sequences, etc., and in the uplink transmission, it is also possible to distinguish different demodulation reference signals by port numbers, scrambling codes, etc., and the embodiments of the present invention are not particularly limited to this, and it is even possible to distinguish different demodulation reference signals by other attributes.

In the embodiment of the present invention, regardless of uplink transmission or downlink transmission, the network device may specify a transmission scheme according to the channel quality, and notify the terminal device of the first mapping relationship corresponding to the transmission scheme through signaling. A specific process of indicating information indicating the first mapping relationship to the terminal device by the network device is described in detail below with reference to fig. 14.

Fig. 14 is a schematic flow chart diagram of a method for data transmission provided by another embodiment of the present invention, shown from the perspective of device interaction. As shown in fig. 14, the method 500 includes:

s510, the network device determines a first mapping relationship according to a predefined mapping rule and a demodulation reference signal resource required by a currently configured transmission scheme, where the first mapping relationship is used to indicate a correspondence relationship between a plurality of demodulation reference signal resources and at least one transmission scheme.

It should be understood that the specific process of the network device determining the first mapping relationship in the method 300 and the method 400 has been described in detail with reference to the drawings, and for brevity, will not be described again here.

S520, the network device sends the indication information of the first mapping relation to the terminal device.

Optionally, S520 specifically includes:

the network device sends an RRC message to the terminal device, where the RRC message carries indication information of the first mapping relationship.

Optionally, S520 specifically includes:

and the network equipment sends the MAC-CE to the terminal equipment, wherein the MAC-CE carries the indication information of the first mapping relation.

Optionally, S520 specifically includes:

and the network equipment sends DCI to the terminal equipment, wherein the DCI carries the indication information of the first mapping relation.

In S520, the terminal device receives the indication information of the first mapping relationship sent by the network device.

S530, the terminal device determines a resource of a demodulation reference signal according to the first mapping relationship and a transmission scheme of the received data stream, where the demodulation reference signal corresponds to the data stream.

It should be understood that the specific process of the terminal device determining the resource of the demodulation reference signal according to the first mapping relationship and the transmission scheme of the data stream has been described in detail in the method 300 and the method 400 with reference to the drawings, and is not described herein again for brevity. The terminal device may correspond to the first terminal device in the method 300 or the method 400, or the terminal device may be any terminal device in the cell.

Therefore, the embodiment of the present invention determines the first mapping relationship through the network device and notifies the terminal device, so that the terminal device can determine the transmission scheme of the monitored data stream according to the received first mapping relationship. Thereby, a dynamic configuration or a semi-static configuration of the first mapping relation can be realized.

Fig. 15 is a schematic block diagram of an apparatus 600 for data transmission according to an embodiment of the present invention. As shown in fig. 15, the apparatus 600 includes: a processing unit 610 and a transmitting unit 620.

In particular, the apparatus 600 may correspond to the network device in the method 300 or the first terminal device in the method 400 for data transmission according to the embodiment of the present invention, and the apparatus 600 may include a unit for performing the method performed by the network device in the method 300 in fig. 3 or the first terminal device in the method 400 in fig. 11. Moreover, the units and other operations and/or functions in the apparatus 600 are respectively for implementing the corresponding flows of the method 300 in fig. 3 or the method 400 in fig. 11, and are not described herein again for brevity.

Fig. 16 is a schematic block diagram of an apparatus 700 for data transmission according to another embodiment of the present invention. As shown in fig. 16, the apparatus 700 includes: a receiving unit 710 and a determining unit 720.

In particular, the apparatus 700 may correspond to a first terminal device in the method 300 or a first network device in the method 400 for data transmission according to an embodiment of the present invention, and the apparatus 700 may include means for performing the method performed by the first terminal device of the method 300 in fig. 3 or the first network device of the method 400 in fig. 11. Moreover, the units and other operations and/or functions in the apparatus 700 are respectively for implementing the corresponding flows of the method 300 in fig. 3 or the method 400 in fig. 11, and are not described herein again for brevity.

Fig. 17 is a schematic block diagram of an apparatus 800 for data transmission according to another embodiment of the present invention. As shown in fig. 17, the apparatus 800 includes: a determining unit 810 and a transmitting unit 820.

In particular, the apparatus 800 may correspond to a network device in the method 500 for data transmission according to an embodiment of the present invention, and the apparatus 800 may include a unit for performing the method performed by the network device in the method 500 in fig. 14. Moreover, each unit and the other operations and/or functions in the apparatus 800 are respectively for implementing the corresponding flow of the method 500 in fig. 14, and are not described herein again for brevity.

Fig. 18 is a schematic block diagram of an apparatus 900 for data transmission according to an embodiment of the present invention. As shown in fig. 18, the apparatus 900 includes: a receiving unit 910 and a determining unit 920.

In particular, the apparatus 800 may correspond to a terminal device in the method 500 for data transmission according to an embodiment of the present invention, and the apparatus 800 may include a unit for performing the method performed by the terminal device in the method 500 in fig. 14. Moreover, each unit and the other operations and/or functions in the apparatus 800 are respectively for implementing the corresponding flow of the method 500 in fig. 14, and are not described herein again for brevity.

Fig. 19 is a schematic block diagram of the apparatus 10 for data transmission according to the embodiment of the present invention. As shown in fig. 19, the apparatus 10 includes: a transceiver 11, a processor 12 and a memory 13. Wherein, the transceiver 11, the processor 12 and the memory 13 communicate with each other via the internal connection path to transmit control and/or data signals, the memory 13 is used for storing a computer program, and the processor 12 is used for calling and running the computer program from the memory 13 to control the transceiver 11 to transmit and receive signals. The memory 13 may be disposed in the processor 12, or may be independent of the processor 12.

In particular, the device 10 may correspond to a network device in the method 300 or a first terminal device in the method 400 for data transmission according to an embodiment of the present invention, and the device 10 may include means for performing the method performed by the network device of the method 300 in fig. 3 or the first terminal device of the method 400 in fig. 11. Moreover, the units and other operations and/or functions in the device 10 are respectively for implementing the corresponding flows of the method 300 in fig. 3 or the method 400 in fig. 11, and are not described again here for brevity.

Alternatively, the device 10 may also correspond to the first terminal device in the method 300 or the first network device in the method 400 for data transmission according to the embodiment of the present invention, and the device 10 may include a unit for performing the method performed by the first terminal device in the method 300 in fig. 3 or the first network device in the method 400 in fig. 11. Moreover, each unit and the other operations and/or functions in the device 10 are respectively for implementing the corresponding flow of the method 300 in fig. 3 or the method 400 in fig. 11, and are not described again here for brevity.

Alternatively, the device 10 may correspond to a network device in the method 500 for data transmission according to an embodiment of the present invention, and the device 10 may include a unit for performing the method performed by the network device of the method 500 in fig. 14. Moreover, each unit and the other operations and/or functions in the device 10 are respectively for implementing the corresponding flow of the method 500 in fig. 14, and are not described herein again for brevity. Alternatively, the device 10 may correspond to a terminal device in the method 500 for data transmission according to an embodiment of the present invention, and the device 10 may include a unit for performing the method performed by the terminal device in the method 500 in fig. 14. Moreover, each unit and the other operations and/or functions in the device 10 are respectively for implementing the corresponding flow of the method 500 in fig. 14, and are not described herein again for brevity.

It should be understood that, in the embodiment of the present invention, the processor may be a Central Processing Unit (CPU), and the processor may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like.

It will also be appreciated that the memory in embodiments of the invention may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of Random Access Memory (RAM) are available, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM), and direct bus RAM (DR RAM).

The above embodiments may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, the above-described embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded or executed on a computer, cause the flow or functions according to embodiments of the invention to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains one or more collections of available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. The semiconductor medium may be a solid state disk.

It should be understood that the term "and/or" herein is merely one type of association relationship that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

It should be understood that, in the various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a U disk, a removable hard disk, a Read Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for data transmission, comprising:

the method comprises the steps that a sending end device carries out precoding on a plurality of demodulation reference signals to obtain a plurality of precoded demodulation reference signals, the resource of each demodulation reference signal in the plurality of demodulation reference signals is associated with the transmission scheme of the corresponding data stream, so that the sending end device determines the transmission scheme of the data stream corresponding to at least one monitored demodulation reference signal, and the at least one demodulation reference signal is not the demodulation reference signal distributed to the receiving end device;

and the sending end equipment sends the plurality of precoding demodulation reference signals and a plurality of data streams corresponding to the precoding demodulation reference signals.

2. The method of claim 1, wherein the resources for the demodulation reference signal comprise at least one of: ports, scrambling codes, orthogonal codes, and orthogonal sequences.

3. The method according to claim 1, wherein the resources of each demodulation reference signal in the plurality of demodulation reference signals are determined according to a predefined first mapping relationship and the transmission scheme of the corresponding data stream, and the first mapping relationship is used to indicate the correspondence relationship between the resources of the plurality of demodulation reference signals and at least one transmission scheme.

4. The method of claim 1, wherein before the transmitting end device precodes the plurality of demodulation reference signals, the method further comprises:

wherein the resource of the demodulation reference signal is determined according to the transmission scheme of the data stream and the first mapping relation.

5. The method according to claim 3 or 4, wherein the resources of the plurality of demodulation reference signals indicated by the first mapping relation are all the resources of the demodulation reference signals allocated by the system.

6. A method for data transmission, comprising:

and the receiving end equipment determines the transmission scheme of the data stream corresponding to the at least one pre-coding demodulation reference signal based on the incidence relation between the resources of the demodulation reference signal and the transmission scheme.

7. The method of claim 6, wherein the method further comprises:

8. The method according to claim 6 or 7, wherein the resources of the demodulation reference signal comprise at least one of: ports, scrambling codes, orthogonal codes, and orthogonal sequences.

9. The method of claim 6, wherein the association relationship between the resources of the demodulation reference signal and the transmission scheme comprises: a first mapping relation for indicating a correspondence relation of resources of a plurality of demodulation reference signals and at least one transmission scheme; and the number of the first and second groups,

and the receiving end equipment determines a transmission scheme corresponding to the resource of the pre-coding demodulation reference signal as the transmission scheme of the data stream according to the predefined first mapping relation.

10. The method of claim 6, wherein the association relationship between the resources of the demodulation reference signal and the transmission scheme comprises: a first mapping relation for indicating a correspondence relation of resources of a plurality of demodulation reference signals and at least one transmission scheme; and the number of the first and second groups,

acquiring the first mapping relation, wherein the first mapping relation is determined according to a predefined mapping rule and a demodulation reference signal resource required by a currently configured transmission scheme;

and determining a transmission scheme of the data stream according to the first mapping relation and the resource of the pre-coding demodulation reference signal.

11. The method according to claim 9 or 10, wherein the resources of the plurality of demodulation reference signals indicated by the first mapping relation are all the resources of the demodulation reference signals allocated by the system.

12. A method for data transmission, comprising:

the network device sends indication information of the first mapping relation to a terminal device, where the first mapping relation is used for the terminal device to determine a transmission scheme of a corresponding data stream according to at least one monitored demodulation reference signal, each demodulation reference signal in the at least one demodulation reference signal corresponds to one data stream in the at least one data stream, and the at least one demodulation reference signal is not a demodulation reference signal allocated to the terminal device.

13. The method of claim 12, wherein the resources of the plurality of demodulation reference signals indicated by the first mapping relation are all resources of system-allocated demodulation reference signals.

14. The method according to claim 12 or 13, wherein the sending the indication information of the first mapping relationship to the terminal device includes:

15. The method according to claim 12 or 13, wherein the sending the indication information of the first mapping relationship to the terminal device includes:

16. The method according to claim 12 or 13, wherein the sending the indication information of the first mapping relationship to the terminal device includes:

17. A method for data transmission, comprising:

the terminal device determines a transmission scheme of at least one data stream according to the first mapping relation and the at least one monitored demodulation reference signal, wherein each demodulation reference signal in the at least one demodulation reference signal corresponds to one data stream in the at least one data stream, and the at least one demodulation reference signal is not a demodulation reference signal allocated to the terminal device.

18. The method of claim 17, wherein the resources of the plurality of demodulation reference signals indicated by the first mapping relation are all resources of system-allocated demodulation reference signals.

19. The method according to claim 17 or 18, wherein the receiving, by the terminal device, the indication information of the first mapping relationship sent by the network device includes:

20. The method according to claim 17 or 18, wherein the receiving, by the terminal device, the indication information of the first mapping relationship sent by the network device includes:

21. The method according to claim 17 or 18, wherein the receiving, by the terminal device, the indication information of the first mapping relationship sent by the network device includes:

22. An apparatus for data transmission, comprising:

a processing unit, configured to precode a plurality of demodulation reference signals to obtain a plurality of precoded demodulation reference signals, where a resource of each demodulation reference signal in the plurality of demodulation reference signals is associated with a transmission scheme of a corresponding data stream, so that a receiving end device determines a transmission scheme of a data stream corresponding to at least one monitored demodulation reference signal, where the at least one demodulation reference signal is not a demodulation reference signal allocated to the receiving end device;

and a transmitting unit, configured to transmit the plurality of precoded demodulation reference signals and a plurality of data streams corresponding to the precoded demodulation reference signals.

23. The apparatus of claim 22, wherein the resources of the demodulation reference signal comprise at least one of: ports, scrambling codes, orthogonal codes, and orthogonal sequences.

24. The apparatus of claim 22, wherein the resource of the plurality of demodulation reference signals at each demodulation reference signal is determined according to a predefined first mapping relationship and a transmission scheme of the corresponding data stream, and the first mapping relationship is used to indicate the correspondence relationship between the resource of the plurality of demodulation reference signals and at least one transmission scheme.

25. The apparatus according to claim 22, wherein the apparatus further comprises an obtaining unit configured to obtain a first mapping relationship, where the first mapping relationship is determined according to a predefined mapping rule and resources of demodulation reference signals required by a currently configured transmission scheme, and the first mapping relationship is used to indicate a correspondence relationship between resources of multiple demodulation reference signals and at least one transmission scheme;

26. The apparatus according to claim 24 or 25, wherein the resources of the plurality of demodulation reference signals indicated by the first mapping relation are all resources of system-allocated demodulation reference signals.

27. An apparatus for data transmission, comprising:

a receiving unit, configured to monitor at least one pre-coding demodulation reference signal that is not allocated to the receiving unit, where the at least one pre-coding demodulation reference signal is obtained by a sending end device pre-coding the at least one demodulation reference signal, and each demodulation reference signal corresponds to a data stream;

a determining unit, configured to determine a transmission scheme of a data stream corresponding to the at least one precoded demodulation reference signal based on an association relationship between resources of the demodulation reference signal and the transmission scheme.

28. The apparatus of claim 27, wherein the determining unit is further configured to determine a channel matrix corresponding to at least one precoded demodulation reference signal based on the at least one precoded demodulation reference signal and a corresponding transmission scheme.

29. The apparatus according to claim 27 or 28, wherein the resources of the demodulation reference signal comprise at least one of: ports, scrambling codes, orthogonal codes, and orthogonal sequences.

30. The apparatus of claim 27, wherein the association relationship between the resources of the demodulation reference signal and the transmission scheme comprises a first mapping relationship, and the first mapping relationship is used to indicate a correspondence relationship between the resources of the demodulation reference signal and at least one transmission scheme;

the determining unit is specifically configured to determine, according to a predefined first mapping relationship, that a transmission scheme corresponding to the resource of the precoding demodulation reference signal is the transmission scheme of the data stream.

31. The apparatus of claim 27, wherein the association relationship between the resources of the demodulation reference signal and the transmission scheme comprises a first mapping relationship, and the first mapping relationship is used to indicate a correspondence relationship between the resources of the demodulation reference signal and at least one transmission scheme;

the device further comprises an obtaining unit, configured to obtain the first mapping relationship, where the first mapping relationship is determined according to a predefined mapping rule and a resource of a demodulation reference signal required by a currently configured transmission scheme;

the determining unit is specifically configured to determine a transmission scheme of the data stream according to the first mapping relationship and the word eye of the precoded demodulation reference signal.

32. The apparatus according to claim 30 or 31, wherein the resources of the plurality of demodulation reference signals indicated by the first mapping relation are all resources of system-allocated demodulation reference signals.

33. An apparatus for data transmission, comprising:

a determining unit, configured to determine a first mapping relationship according to a predefined mapping rule and a resource of a demodulation reference signal required by a currently configured transmission scheme, where the first mapping relationship is used to indicate a correspondence relationship between resources of multiple demodulation reference signals and at least one transmission scheme;

a sending unit, configured to send, to a terminal device, indication information of the first mapping relationship, where the first mapping relationship is used for the terminal device to determine a transmission scheme of a corresponding data stream according to at least one monitored demodulation reference signal, where each demodulation reference signal in the at least one demodulation reference signal corresponds to one data stream in the at least one data stream, and the at least one demodulation reference signal is not a demodulation reference signal allocated to the terminal device.

34. The apparatus of claim 33, wherein the resources of the plurality of demodulation reference signals indicated by the first mapping relation are all resources of system-allocated demodulation reference signals.

35. The apparatus according to claim 33 or 34, wherein the sending unit is specifically configured to send a radio resource control, RRC, message to the terminal device, where the RRC message carries the indication information of the first mapping relationship.

36. The apparatus according to claim 33 or 34, wherein the sending unit is specifically configured to send a media access control, MAC, control information element, CE, to the terminal device, where the MAC-CE carries indication information of the first mapping relationship.

37. The apparatus according to claim 33 or 34, wherein the sending unit is specifically configured to send downlink control information DCI to the terminal device, where the DCI carries the indication information of the first mapping relationship.

38. An apparatus for data transmission, comprising:

a receiving unit, configured to receive indication information of a first mapping relationship sent by a network device, where the first mapping relationship is used to indicate a correspondence relationship between a plurality of demodulation reference signals and at least one transmission scheme;

a determining unit, configured to determine a transmission scheme of at least one data stream according to the first mapping relationship and the at least one monitored demodulation reference signal, where each demodulation reference signal in the at least one demodulation reference signal corresponds to one data stream in the at least one data stream, and the at least one demodulation reference signal is not a demodulation reference signal allocated to the apparatus.

39. The apparatus of claim 38, wherein the resources of the plurality of demodulation reference signals indicated by the first mapping relation are all resources of system-allocated demodulation reference signals.

40. The apparatus according to claim 38 or 39, wherein the receiving unit is specifically configured to receive a radio resource control, RRC, message sent by a network device, where the RRC message carries the indication information of the first mapping relationship.

41. The apparatus according to claim 38 or 39, wherein the receiving unit is specifically configured to receive a media access control, MAC, control information element, CE, sent by a network device, where the MAC-CE carries indication information of the first mapping relationship.

42. The apparatus according to claim 38 or 39, wherein the receiving unit is specifically configured to receive downlink control information DCI sent by the network device, where the DCI carries indication information of the first mapping relationship.