CN116762304A

CN116762304A - Method and device for transmitting downlink signal

Info

Publication number: CN116762304A
Application number: CN202180089887.4A
Authority: CN
Inventors: 颜矛
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-01-08
Filing date: 2021-01-08
Publication date: 2023-09-15
Also published as: WO2022147802A1

Abstract

The application discloses a downlink signal transmission method and device, which are used for solving the problem that transmission resources are consumed for transmitting demodulation reference signals. The method comprises the following steps: the network equipment sends a downlink control channel and a first demodulation reference signal to the terminal equipment, wherein the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling a downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel; and the network equipment sends the downlink data channel to the terminal equipment.

Description

Method and device for transmitting downlink signal

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method and an apparatus for transmitting a downlink signal.

Background

In a wireless communication system, wireless signal transmission is affected by channel fading, and a receiving end needs channel information to recover a channel. In general, the receiving end can acquire channel information through demodulation reference signals (demodulation reference signal, DMRS), so as to demodulate wireless signals carried by the channels.

At present, a downlink signal is generally set to be associated with a DMRS, and a downlink data channel and a downlink control channel both have the associated DMRS. And in the downlink transmission, different downlink signals are transmitted together with the associated DMRS, and the receiving end can demodulate the downlink signals transmitted together with the DMRS based on the DMRS. The DMRS occupies resource elements, consumes transmission resources, and has large signaling overhead.

Disclosure of Invention

The application provides a downlink signal transmission method and a downlink signal transmission device, which aim to realize multiplexing of demodulation reference signals so as to reduce consumption of transmission resources and signaling overhead.

In a first aspect, the present application provides a method for transmitting a downlink signal, including: the network equipment sends a downlink control channel and a first demodulation reference signal to the terminal equipment, wherein the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling a downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel; and the network equipment sends the downlink data channel to the terminal equipment. The demodulation reference signals associated with the downlink control channels can be set to be used for demodulating the downlink data channels, multiplexing of the demodulation reference signals is achieved, and consumption of transmission resources and signaling overhead are reduced.

In an alternative implementation, one or more of the following conditions are satisfied: the downlink control channel and the downlink data channel adopt the same transmission mode; the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode. By setting the downlink data channel to be the same as the downlink control channel for scheduling the downlink data channel and the demodulation reference signal transmission mode associated with the downlink control channel, the demodulation reference signal associated with the downlink control channel can be used for demodulating the downlink data channel, so that multiplexing of the demodulation reference signal is realized.

In an alternative implementation, the method further includes: the network device sends first indication information to the terminal device, wherein the first indication information is used for indicating one or more of the following: the downlink control channel and the downlink data channel adopt the same transmission mode; the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.

In the application, the network equipment informs the terminal equipment through the first indication information, the downlink data channel is the same as the downlink control channel for scheduling the downlink data channel and the demodulation reference signal transmission mode related to the downlink control channel, multiplexing of the demodulation reference signal is realized, and the terminal equipment can demodulate the downlink data channel according to the demodulation reference signal related to the downlink control channel. The network equipment is not required to issue demodulation reference signals associated with the downlink control channels, so that the consumption of transmission resources can be reduced, and the signaling overhead is reduced.

In an alternative implementation, the same transmission means includes the same transmission resources, the same precoding and the same precoding granularity.

In an alternative implementation, the method further includes: and the network equipment sends the second demodulation reference signal associated with the downlink data channel to the terminal equipment. In this way, the terminal device can demodulate the downlink data channel by combining the first demodulation reference signal and the second demodulation reference signal, so as to improve the detection performance of the downlink data channel.

In an alternative implementation, the method further includes: the network device sends second indication information to the terminal device, wherein the second indication information is used for indicating a time domain resource position and/or a frequency domain resource position occupied by the second demodulation reference signal. In this way, the time-frequency resource position where the second demodulation reference signal is located is indicated to the terminal device directly in a display manner.

In an alternative implementation, the method further includes: the network equipment sends second indication information to the terminal equipment, wherein the second indication information comprises information for indicating the first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel (for example, a time domain resource starting position of the downlink control channel or a time domain resource ending position of the downlink control channel), or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel (or a time domain resource ending position). In this way, the location of the time domain resource where the second demodulation reference signal is located can be indicated to the terminal device indirectly or implicitly, and the terminal device can know the location of the second demodulation reference signal based on the time domain resource location where the first demodulation reference signal/downlink control channel is located and combined with the first time domain offset.

In an alternative implementation, the method further includes: the network device sends third indication information to the terminal device, wherein the third indication information is used for indicating one or more of precoding granularity of the downlink control channel, precoding granularity of the first demodulation reference signal, precoding granularity of the downlink data channel and precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel. In this way, the terminal device can demodulate part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signals, so as to realize multiplexing of the demodulation reference signals, and reduce transmission resources occupied by the second demodulation reference signals associated with the downlink data channels and signaling overhead.

In an alternative implementation, the precoding granularity of the downlink control channel is related to the precoding granularity of the downlink data channel; or, the precoding granularity of the downlink control channel is related to the precoding granularity of the second demodulation reference signal; or, the precoding granularity of the first demodulation reference signal is related to the precoding granularity of the downlink data channel; alternatively, the precoding granularity of the first demodulation reference signal is correlated with the precoding granularity of the second demodulation reference signal.

In a second aspect, the present application provides a method for transmitting a downlink signal, including: the method comprises the steps that a terminal device receives a downlink control channel and a first demodulation reference signal from a network device, wherein the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling a downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel; the terminal equipment demodulates the downlink control channel according to the first demodulation reference signal; the terminal equipment receives the downlink data channel from the network equipment and demodulates the downlink data channel according to the first demodulation reference signal. The demodulation reference signals associated with the downlink control channels can be set to be used for demodulating the downlink data channels, multiplexing of the demodulation reference signals is achieved, and consumption of transmission resources and signaling overhead are reduced.

In an optional implementation manner, when the terminal device receives a downlink control channel from a network device and receives (acquires) the downlink data channel from the network device based on the downlink control channel, the terminal device first demodulates the downlink control channel and the downlink data channel according to the first demodulation reference signal; or, the terminal device may first receive the downlink control channel from the network device, i.e. first demodulate the downlink control channel according to the first demodulation reference signal, then receive (acquire) the downlink data channel from the network device based on the control information in the downlink control channel, and demodulate the downlink data channel according to the first demodulation reference signal.

In an alternative implementation, the method further includes: the terminal device receives first indication information from the network device, wherein the first indication information is used for indicating one or more of the following: the downlink control channel and the downlink data channel adopt the same transmission mode; the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.

In an alternative implementation, the same transmission means comprises the same transmission resources, the same precoding and the same precoding granularity.

In an alternative implementation, the method further includes: the terminal equipment receives a second demodulation reference signal associated with the downlink data channel from the network equipment; and the terminal equipment demodulates the downlink data channel according to the first demodulation reference signal and the second demodulation reference signal. In this way, the terminal device can demodulate the downlink data channel by combining the first demodulation reference signal and the second demodulation reference signal, so as to improve the detection performance of the downlink data channel.

In an alternative implementation, the method further includes: and receiving second indication information from the network equipment, wherein the second indication information is used for indicating the time domain resource position and/or the frequency domain resource position occupied by the second demodulation reference signal. In this way, the time-frequency resource position where the second demodulation reference signal is located is indicated to the terminal device directly in a display manner.

In an alternative implementation, the method further includes: receiving second indication information from the network device, the second indication information including information indicating a first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel (for example, a time domain resource starting position of the downlink control channel or a time domain resource ending position of the downlink control channel), or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel (or a time domain resource ending position). In this way, the location of the time domain resource where the second demodulation reference signal is located can be indicated to the terminal device indirectly or implicitly, and the terminal device can know the location of the second demodulation reference signal based on the time domain resource location where the first demodulation reference signal/downlink control channel is located and combined with the first time domain offset.

In an alternative implementation, the method further includes: the terminal equipment receives third indication information from the network equipment, wherein the third indication information is used for indicating one or more of precoding granularity of the downlink control channel, precoding granularity of the first demodulation reference signal, precoding granularity of the downlink data channel and precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel. In this way, the terminal device can demodulate part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signals, so as to realize multiplexing of the demodulation reference signals, and reduce transmission resources occupied by the second demodulation reference signals associated with the downlink data channels and signaling overhead.

In an alternative implementation manner, the terminal device demodulates the downlink data channel according to the first demodulation reference signal, including: and the terminal equipment demodulates part or all of the downlink data channels sent by the network equipment according to the first demodulation reference signal and the third indication information.

In an optional implementation manner, the terminal device demodulates part or all of the downlink data channels sent by the network device according to the first demodulation reference signal and the third indication information, and includes: the terminal equipment determines a transmission mode of the downlink data channel and a transmission mode of the first demodulation reference signal according to third indication information and the downlink control channel demodulated by the first demodulation reference signal; the downlink data channel and the second demodulation reference signal adopt the same transmission mode, the first demodulation reference signal and the downlink control channel adopt the same transmission mode, and the transmission mode comprises precoding, precoding granularity and transmission resources.

If the transmission mode of the downlink data channel is the same as the transmission mode of the first demodulation reference signal, the terminal equipment demodulates all of the downlink data channels according to the first demodulation reference signal; and if the transmission mode of the downlink data channel is partially the same as that of the first demodulation reference signal, the terminal equipment demodulates the part in the downlink data channel according to the first demodulation reference signal.

In an optional implementation manner, the terminal device demodulates part or all of the downlink data channels sent by the network device according to the first demodulation reference signal and the third indication information, and includes: the terminal equipment determines that the precoding granularity of the downlink data channel is the same as the precoding granularity of the first demodulation reference signal according to the third indication information; the terminal equipment demodulates all downlink data channels sent by the network equipment according to the first demodulation reference signal; or the terminal equipment demodulates a downlink data channel which is sent by the network equipment according to the first demodulation reference signal and occupies the same frequency domain resource with the first demodulation reference signal.

In an optional implementation manner, the terminal device demodulates part or all of the downlink data channels sent by the network device according to the first demodulation reference signal and the third indication information, and includes: the terminal equipment determines that the precoding granularity of the downlink data channel is different from that of the first demodulation reference signal according to the third indication information, and the precoding resource block group of the downlink data channel is partially overlapped with that of the first demodulation reference signal; and the terminal equipment demodulates the downlink data channels in the precoding resource block group of the overlapping part according to the first demodulation reference signals in the precoding resource block group of the overlapping part.

In a third aspect, the present application provides a transmission apparatus for a downlink signal, applied to a network device, where the apparatus includes: the processing module is used for generating a downlink control channel, a first demodulation reference signal and a downlink data channel, wherein the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling the downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel; the communication module is used for sending the downlink control channel and the first demodulation reference signal to the terminal equipment; the communication module is further configured to send the downlink data channel to the terminal device. The demodulation reference signals associated with the downlink control channels can be set to be used for demodulating the downlink data channels, multiplexing of the demodulation reference signals is achieved, and consumption of transmission resources and signaling overhead are reduced.

In an alternative implementation manner, the communication module is further configured to send first indication information to the terminal device, where the first indication information is used to indicate one or more of the following: the downlink control channel and the downlink data channel adopt the same transmission mode; the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.

In an alternative implementation manner, the communication module is further configured to send the second demodulation reference signal associated with the downlink data channel to the terminal device. In this way, the terminal device can demodulate the downlink data channel by combining the first demodulation reference signal and the second demodulation reference signal, so as to improve the detection performance of the downlink data channel.

In an optional implementation manner, the communication module is further configured to send second indication information to the terminal device, where the second indication information is used to indicate a time domain resource location and/or a frequency domain resource location occupied by the second demodulation reference signal.

In an optional implementation manner, the communication module is further configured to send second indication information to the terminal device, where the second indication information includes information for indicating the first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel (for example, a time domain resource starting position of the downlink control channel or a time domain resource ending position of the downlink control channel), or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel (or a time domain resource ending position). In this way, the time domain resource position where the second demodulation reference signal is located can be indirectly or implicitly indicated to the terminal device, and the terminal device can know the position of the second demodulation reference signal based on the time domain resource position where the first demodulation reference signal/downlink control channel is located and combined with the first time domain offset.

In an optional implementation manner, the communication module is further configured to send third indication information to the terminal device, where the third indication information is used to indicate one or more of a precoding granularity of the downlink control channel, a precoding granularity of the first demodulation reference signal, a precoding granularity of the downlink data channel, and a precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel. In this way, the terminal device can demodulate part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signals, so as to realize multiplexing of the demodulation reference signals, and reduce transmission resources occupied by the second demodulation reference signals associated with the downlink data channels and signaling overhead.

In a fourth aspect, the present application provides a downlink signal transmission apparatus, applied to a terminal device, where the apparatus includes: the communication module is used for receiving a downlink control channel and a first demodulation reference signal from the network equipment, wherein the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling a downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel; the processing module is used for demodulating the downlink control channel according to the first demodulation reference signal; the communication module is further configured to receive the downlink data channel from the network device; the processing module is further configured to demodulate the downlink data channel according to the first demodulation reference signal. The demodulation reference signals associated with the downlink control channels can be set to be used for demodulating the downlink data channels, multiplexing of the demodulation reference signals is achieved, and consumption of transmission resources and signaling overhead are reduced.

In an alternative implementation manner, the communication module is specifically configured to receive a downlink control channel from a network device, and receive (acquire) the downlink data channel from the network device based on the downlink control channel; the processing module is specifically configured to demodulate a downlink control channel and a downlink data channel according to the first demodulation reference signal; or the communication module may first receive a downlink control channel from the network device, and the processing module first demodulates the downlink control channel according to the first demodulation reference signal; the communication module receives (acquires) the downlink data channel from the network device based on the control information in the downlink control channel, and the processing module demodulates the downlink data channel according to the first demodulation reference signal.

In an alternative implementation, the communication module is further configured to receive first indication information from the network device, where the first indication information is used to indicate one or more of the following: the downlink control channel and the downlink data channel adopt the same transmission mode; the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.

In an alternative implementation, the communication module is further configured to receive a second demodulation reference signal associated with the downlink data channel from the network device; the processing module is further configured to demodulate the downlink data channel according to the first demodulation reference signal and the second demodulation reference signal. In this way, the terminal device can demodulate the downlink data channel by combining the first demodulation reference signal and the second demodulation reference signal, so as to improve the detection performance of the downlink data channel.

In an optional implementation manner, the communication module is further configured to send second indication information to the terminal device, where the second indication information is further used to indicate a time domain resource location and/or a frequency domain resource location occupied by the second demodulation reference signal.

In an optional implementation manner, the communication module is further configured to send second indication information to the terminal device, where the second indication information includes information for indicating the first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel (for example, a time domain resource starting position of the downlink control channel or a time domain resource ending position of the downlink control channel), or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel (or a time domain resource ending position). In this way, the location of the time domain resource where the second demodulation reference signal is located can be indicated to the terminal device indirectly or implicitly, and the terminal device can know the location of the second demodulation reference signal based on the time domain resource location where the first demodulation reference signal/downlink control channel is located and combined with the first time domain offset.

In an optional implementation manner, the communication module is further configured to receive third indication information from the network device, where the third indication information is used to indicate one or more of a precoding granularity of the downlink control channel, a precoding granularity of the first demodulation reference signal, a precoding granularity of the downlink data channel, and a precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel. In this way, the terminal device can demodulate part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signals, so as to realize multiplexing of the demodulation reference signals, and reduce transmission resources occupied by the second demodulation reference signals associated with the downlink data channels and signaling overhead.

In an optional implementation manner, the processing module is further configured to demodulate part or all of the downlink data channels sent by the network device according to the first demodulation reference signal and the third indication information.

In an alternative implementation, the processing module is specifically configured to: determining a transmission mode of the downlink data channel and a transmission mode of the first demodulation reference signal according to third indication information and the downlink control channel demodulated by the first demodulation reference signal; the downlink data channel and the second demodulation reference signal adopt the same transmission mode, the first demodulation reference signal and the downlink control channel adopt the same transmission mode, and the transmission mode comprises precoding, precoding granularity and transmission resources. If the transmission mode of the downlink data channel is the same as the transmission mode of the first demodulation reference signal, demodulating all of the downlink data channels according to the first demodulation reference signal; and if the transmission mode of the downlink data channel is partially the same as that of the first demodulation reference signal, demodulating the part in the downlink data channel according to the first demodulation reference signal.

In an alternative implementation, the processing module is specifically configured to: and determining that the precoding granularity of the downlink data channel is the same as the precoding granularity of the first demodulation reference signal according to the third indication information. Demodulating all downlink data channels sent by the network equipment according to the first demodulation reference signal; or the terminal equipment demodulates a downlink data channel which is sent by the network equipment according to the first demodulation reference signal and occupies the same frequency domain resource with the first demodulation reference signal.

In an alternative implementation, the processing module is specifically configured to: and according to the third indication information, determining that the precoding granularity of the downlink data channel is different from that of the first demodulation reference signal, and the precoding resource block group of the downlink data channel is partially overlapped with that of the first demodulation reference signal. Demodulating a downlink data channel in the pre-coding resource block group of the overlapping part according to a first demodulation reference signal in the pre-coding resource block group of the overlapping part.

In a fifth aspect, the present application provides a communications device comprising a processor coupled to a memory for storing a computer program or instructions for execution by the processor to perform the respective implementation of the first or second aspects described above. The memory may be located within the device or may be located external to the device. The number of processors is one or more.

In a sixth aspect, the present application provides a communication apparatus comprising: a processor for communicating with other devices, and interface circuitry for implementing the methods of the first or second aspects described above.

In a seventh aspect, the present application provides a communication system comprising: a network device for performing the above-mentioned first aspect and a terminal device for performing the above-mentioned second aspect.

In an eighth aspect, the present application further provides a chip system, including: a processor, configured to perform each implementation method of the first aspect or the second aspect.

In a ninth aspect, the application also provides a computer program product comprising a computer program which, when run, causes the implementation of the methods of the first or second aspects described above.

In a tenth aspect, the present application also provides a computer readable storage medium having stored therein a computer program or instructions which, when run on a computer, implement the respective implementation methods of the first or second aspects described above.

The technical effects achieved by the fifth to tenth aspects are referred to the technical effects achieved by the corresponding technical aspects of the first to second aspects, and the detailed description is not repeated here.

Drawings

Fig. 1 is a schematic diagram of a transmission resource structure;

fig. 2 is a schematic diagram of a distribution of demodulation reference signals according to an embodiment of the present application;

fig. 3 is a schematic diagram of a communication system architecture according to an embodiment of the present application;

FIG. 4 is a schematic diagram of an interaction flow for transmitting information between a network device and a terminal device;

fig. 5 is a schematic flow chart of a downlink signal transmission method according to an embodiment of the present application;

fig. 6 is a second flowchart of a downlink signal transmission method according to an embodiment of the present application;

fig. 7 is a third schematic flow chart of a downlink signal transmission method according to an embodiment of the present application;

fig. 8a is a second schematic diagram of a distribution of demodulation reference signals according to an embodiment of the present application;

fig. 8b is a third schematic diagram of a distribution of demodulation reference signals according to an embodiment of the present application;

fig. 9a is one of precoding diagrams of demodulation reference signals according to an embodiment of the present application;

fig. 9b is a second precoding diagram of a demodulation reference signal according to an embodiment of the present application;

fig. 9c is a third diagram illustrating precoding of a demodulation reference signal according to an embodiment of the present application;

fig. 9d is a schematic diagram illustrating precoding of demodulation reference signals according to an embodiment of the present application;

Fig. 10 is a flowchart of a downlink signal transmission method according to an embodiment of the present application;

fig. 11 is a fifth flowchart of a downlink signal transmission method according to an embodiment of the present application;

fig. 12 is a block diagram of a downlink signal transmission device according to an embodiment of the present application;

fig. 13 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 14 is a second schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

Embodiments of the present application may be applied to wireless communication networks, such as 4G networks (e.g., LTE), 5G networks, future networks, etc., and the present application will be described in further detail with reference to the accompanying drawings.

First, some terms provided in the present application will be explained for convenience of understanding by those skilled in the art:

(1) Network device and terminal device

The network device may communicate with the terminal device to provide wireless access services to the terminal device. The network device may also be referred to as a base station device, also as a base station, a relay station, or AN access point (AN), etc. The network device may be, for example, a base transceiver station (base transceiver station, BTS) in a global system for mobile communications (global system for mobile communication, GSM) or code division multiple access (code division multiple access, CDMA) network, an NB (NodeB) in a wideband code division multiple access (wideband code division multiple access, WCDMA) network, or an eNB or eNodeB (Evolutional NodeB) in a long term evolution (long term evolution, LTE) system. The network device may also be a wireless controller in the context of a cloud wireless access network (cloud radio access network, CRAN). The network device may also be a base station device in a 5G network or a network device in a future evolved PLMN network. The network device may also be a wearable device or an in-vehicle device.

The terminal device may also be referred to as a User Equipment (UE), an access terminal, a terminal unit, a terminal station, a mobile station, a remote terminal, a mobile device, a mobile terminal, a wireless communication device, a terminal agent, a terminal apparatus, or the like. By way of example, the terminal device may be a cellular telephone, a cordless telephone, a session initiation protocol (session initiation protocol, SIP) phone, a wireless local loop (wireless Local Loop, WLL) station, a personal digital assistant (personal digital assistant, PDA), a handheld device with wireless communication capabilities, a computing device or other processing device connected to a wireless modem, an entire car, an in-vehicle device or an in-vehicle module, a wearable device, a terminal device in a 5G network or a terminal device in a future evolved PLMN network, etc.

(2) Downlink control channel and downlink data channel

In the downlink transmission process, a signal sent by the network device to the terminal device is also called a downlink signal, and the downlink signal includes a downlink control signal and a downlink data signal. The downlink control channel in the embodiment of the present application is used to refer to a downlink control signal, that is, the downlink control channel may also be understood as a downlink control signal, and the downlink control channel may be a physical downlink control channel (physical downlink control channel, PDCCH). The downlink control channel in the embodiment of the present application is used to refer to a downlink data signal, that is, a downlink data channel may also be understood as a downlink data signal, and the downlink data channel may be a physical downlink shared channel (physical downlink shared channel, PDSCH). For higher layers, these channels correspond to Resource Elements (REs) that carry bit information of the upper layer (e.g., layer two); for air interfaces, these channels carry wireless signals.

The downlink control channel is used for scheduling a downlink data channel, for example, a PDCCH is used for transmitting scheduling and configuration information related to a PDSCH, downlink control information (downlink control information, DCI) is carried in the PDCCH, and the DCI is used for indicating configuration information (for example, time/frequency position, modulation information and the like) of the PDSCH.

(3) Random access

The downlink transmission related to the embodiment of the application comprises a process that the network equipment issues a message to the terminal equipment in a Random Access (RA) process and downlink transmission between the network equipment and the terminal equipment after the terminal equipment is accessed.

Wherein, random access is an information interaction mechanism (or procedure) for devices not accessing the network to establish connection with the network in a communication system with access control in LTE or 5G. Since the random access procedure is carried by a random access channel (random access channel, RACH), the RA and RACH mixed representation is also often used in protocols and spoken language. Random access is classified into contention-based random access and non-contention random access. Contention-based random access is typically divided into 4 steps, each step corresponding to a message: including message 1, message 2, message 3, message 4, carrying different signaling or information, respectively. There is only the first 2 steps of non-contention based random access. In addition, in order to reduce the access time of the 4-step contention-based random access, there is a further 2-step random access. In 2-step random access, it consists of two messages, message a and message B, where message a includes a preamble and first data information (e.g., similar to message 1 and message 3 in 4-step random access), and message B includes contention resolution and uplink scheduling (e.g., similar to message 2 and message 4 in 4-step random access).

Random access opportunity: the random access opportunity is also called random access resource (RACH resource), random access opportunity (RACH timing/RACH transmission occasion/RACH reporting unit/RACH challenge, RO), and refers to a time, frequency resource used to carry one or more random access preambles. Logically, one random access opportunity is used to carry information/signals of a physical random access channel (physical random access channel, PRACH). Sometimes equivalently referred to as physical random access (RO), physical random access resource (PRACH resource).

Message 1 (message 1, msg 1): i.e., random access preamble (preamble or sequence), is carried over a physical random access channel (physical random access channel, PRACH). Typically for the terminal device to initiate a connection request, a handover request, a synchronization request, a scheduling request to the network device.

Message 2 (message 2, msg 2): also known as random access response (random access response, RAR) messages. In response to the received message 1, the network device side may respond to a plurality of Msg1 in one message 2. For a single random access preamble, there is a specific random access response message at the MAC. The network device often encapsulates the responses of all random access preambles detected on one random access opportunity together to form one Msg2. I.e. after the terminal device sends the random access preamble, it searches the corresponding message 2 for the random access response message corresponding to the random access preamble sent by itself, and ignores the response messages for other random access preambles. If the network side receives the message 1, at least one of the following information is encapsulated into a random access response (random access response, RAR) transmission: index of message 1 (random access preamble identity, RAPID), uplink grant (uplink grant), time advance (timing advance), temporary cell-radio network temporary identity (temporary cell radio network temporary identity, TC-RNTI), etc. The network side may be within the same Msg2 and respond to multiple Msg1 at the same time, i.e. contain multiple RARs.

Message 3 (message 3, msg 3): also referred to as first uplink scheduled transmission, is a retransmission scheduled by UL grant in message 2, or DCI scrambled by TC-RNTI. The Msg3 transmission content is a higher layer message, such as a connection establishment request message (specifically, may be identification information of the user initiating the connection request). The message is used for contention resolution, if multiple different devices use the same Msg1 for random access, it can be determined jointly by Msg3 and Msg4 whether there is a collision. Definition of Msg3 on protocol: message transmitted on UL-SCH (uplink shared channel) containing a C-RNTI MAC (Medium access control) CE (control element) or CCCH (Common Control Channel) SDU (Service Data Unit), submitted from upper layer and associated with the UE Contention Resolution Identity, as part of a Random Access procedure. The transmission of message 3 has retransmission and power control (i.e., there is power control information in UL grant for scheduling initial transmission or retransmission).

Message 4 (message 4, msg 4): for contention resolution. Typically containing CCCH SDUs carried in message 3, if the device detects a CCCH SDU sent by itself in message 4, it considers that contention random access is successful and proceeds with the next communication procedure. Message 4 has retransmission, i.e. there is a corresponding physical uplink control channel (physical uplink control channel, PUCCH) to transmit feedback information (whether message 4 was successfully detected) and the device has power control in PUCCH to transmit the feedback information.

The transmit power, also referred to as the output power. May be defined as the measured output power over all or part of the supported frequency or frequency band or bandwidth at a given time and/or period. For example, the time of measurement is at least 1ms, and for example, the time of measurement is at least one slot corresponding to a certain subcarrier interval. In one embodiment, the measured time is at least 1ms of power acquired.

(4) Modulation and demodulation

Modulation is the process of processing information from a signal source onto a carrier wave to bring it into a form suitable for channel transmission. The different modes correspond to different modulation methods, such as whether multicarrier modulation or single carrier modulation, quadrature amplitude modulation (quadrature Amplitude modulation, QAM), pulse amplitude modulation (pulse amplitude modulation, PAM), phase shift keying (phase shift keying, PSK) modulation, amplitude keying (amplitude shift keying, ASK) modulation, etc. Demodulation, the inverse of modulation, recovers the original data bits or symbols from the signal. Demodulation may also sometimes be referred to as detection.

(5) Reference signal, demodulation reference signal

A Reference Signal (RS) is used to obtain a known signal that is affected by external factors (e.g., spatial channel, non-idealities of a transmitting or receiving device) in signal transmission, and perform channel estimation, auxiliary signal demodulation, detection, and so on. The transmitting end (or receiving end) knows or can infer the time and frequency location of the reference signal, and other wireless signals/symbols carried on that time and frequency, etc., according to a predetermined rule. According to the functional division, the reference signals include demodulation reference signals (demodulation reference signal, DMRS), channel state information reference signals (channel state information reference signal, CSI-RS), phase tracking reference signals (phase tracking reference signal, PTRS), channel sounding reference signals (sounding reference signal, SRS), and the like. The DMRS and the CSI-RS are used for acquiring channel information, and the PTRS is used for acquiring phase change information.

In the embodiment of the application, the application of the demodulation reference signal DMRS in the downlink transmission process is focused. The downlink signal sent by the network device is affected by channel fading, and the terminal device can recover the channel by acquiring channel information through the DMRS, so as to demodulate the downlink signal according to the channel information acquired by the DMRS.

Typically, the DMRS sent by the network device is known to the terminal device or may be inferred according to a predetermined rule, and as an implementation manner, the terminal device may perform channel estimation through a linear channel model according to the DMRS received from the network device and the DMRS sent by the network device. The linear channel model is as follows: y=hx+n; wherein y is a signal received by the receiving end, and may be DMRS received by the terminal device; h represents a channel, or may be understood as channel information; x is a signal sent by a sending end, and can be a DMRS sent by a network device; n is noise and may be a set known quantity. The terminal device can then infer, based on the result of the channel estimation, the downstream signal transmitted by the network device over the channel, i.e. the terminal device can recover x based on the channel H, e.g. ignore the channel noise, x=h ^-1 And y. Here x indicates a downlink signal sent by the network device, the downlink signal also goes through the channel H, and y indicates a downlink signal received by the terminal device.

(6) Precoding and codebook

In a communication system having multiple antennas, such as a multiple input multiple output (multiple input multiple output, MIMO) system, signals from multiple transmit antennas are superimposed on any one of the receive antennas, so that the method of transmitting signals at the transmitting end affects the performance of the system, and is often complex when the transmitting end recovers the transmitted signals that have undergone MIMO channels. In this context, precoding can be introduced to deform the linear channel model into: y=hpx+n, where y is the received signal, H is the MIMO channel, x is the transmitted signal, n is noise, and P indicates precoding. As an implementation, P is selectable from a predefined set of matrices (or vectors), which is called Codebook (Codebook). The method by which the transmitting end transmits the signal is also called a codebook-based transmission method. As another implementation manner, if the transmitting end can learn all information of H, and P can also be acquired at the transmitting end, a method of transmitting a signal by the transmitting end is also called a non-codebook (NCB) method. Precoding has two modes, open loop or closed loop. In an open loop mode, the transmitting end determines the transmitted precoding codebook by itself. In a closed loop mode, the transmitting end determines a transmitted precoding codebook based on feedback information and/or indication information of the receiving end. Precoding (Precoding) is introduced to reduce overhead, maximally improve system capacity of MIMO, and reduce complexity of realization of eliminating inter-channel effects at a receiving end. However, precoding is introduced, and channel estimation is performed by DMRS for the receiving end, except that the estimated channel is actually the HP to which precoding is introduced by the transmitting end definition. The transmitting end can be specifically a network device and the receiving end can be specifically a terminal device in the downlink transmission process.

(7) Transmission resources

The transmission resources involved in the embodiment of the application comprise time domain resources and frequency domain resources. Wherein, the time domain resource may refer to any one of the following: a slot, or a bundle of multiple slots, 1 slot comprising a number of consecutive orthogonal frequency division multiplexing (orthogonal frequency divided multiplexing, OFDM) symbols, the number of OFDM symbols being related to the subcarrier spacing (Subcarrier spacing, SCS). The frequency domain resource may refer to any one of the following: resource blocks, resource block groups, precoding resource block groups. Wherein, resource Block (RB): also referred to as physical resource blocks (physical resource block, PRBs), are the basic units of frequency resources in an OFDM-based communication system. One resource block is generally composed of N Resource Elements (REs), which are also called one subcarrier. Where N is typically 12. Several resource blocks constitute one resource block group (resource block group, RBG), or also called physical resource block group. In general, precoding is performed in units of resource blocks or resource block groups, and a basic unit for performing precoding transmission is also called a precoding resource block group (Precoding Resource Block Group, PRG). One precoding resource block group may be not smaller than one resource block group. The number of resource blocks RB or resource element groups REGs included in the precoding resource block group may be represented by a precoding granularity.

For PDCCH, the composition of N Resource Elements (REs) may also be referred to as a resource element group (resource element group, REG).

(8) Controlling resource collections and search spaces

The transmission resources involved in the downlink transmission process may be divided into a control region available for transmitting a downlink control channel and a data region available for transmitting a downlink data channel. A schematic structure of a transmission resource is shown in fig. 1, and the transmission resource distinguishes between a control area and a data area. The control area contains time domain resources and frequency domain resources which can be occupied by the downlink control channel, and the data area contains time domain resources and frequency domain resources which can be occupied by the downlink data channel. As one implementation, the location where the PDCCH exists may be determined in the control region and the location where the PDSCH exists may be determined in the data region.

A control-resource set (CORESET) is a block of time-frequency resources within a control region. One core corresponds to a group of terminal devices, or User Equipment (UE). The inclusion of CORESET 1 and CORESET2 in the control region is also illustrated in fig. 1. Illustratively, if CORESET 1 corresponds to UE1, UE2, UE3, and UE4, and CORESET2 corresponds to UE4, UE5, UE6, and UE7. The PDCCHs of UE1, UE2, UE3 and UE4 may be transmitted on CORESET 1 and the PDCCHs of UE4, UE5, UE6 and UE7 may be transmitted on CORESET 2. In addition, a terminal device may also correspond to a plurality of CORESETs, and numerology (parameter sets) on these CORESETs may be the same or different. The parameter set here includes a subcarrier spacing SCS and a Cyclic Prefix (CP) length. For example, there is a correspondence of UE8 to CORESET 1 and CORESET2, and the PDCCH of UE8 may be transmitted on CORESET 1 and/or CORESET 2. For any one of a group of terminal devices corresponding to a CORESET, any one terminal device has a search space (search space) corresponding to the terminal device on the CORESET, where the resource of the search space is less than or equal to the resource of the CORESET. Taking UE1 as an example, the PDCCH of UE1 may be specifically transmitted in the search space corresponding to UE1 on CORESET 1. As noted above, one CORESET may be bound to multiple searchspaces, but one SearchSpace may be bound to only one CORESET.

As one implementation, CORESET is used to indicate the time, frequency range within a time slot where PDCCH may exist. The search space SearchSpace is used to determine the slots and OFDM symbol positions where PDCCH may exist. A core and a SearchSpace are bound together before the PDCCH configuration can be determined.

The main parameter configuration of the control resource set is described below in conjunction with table 1.

TABLE 1

Further explanation is made regarding CCEs and REGs. One CCE is composed of 6 REGs, one REG corresponding to 1 resource block RB on one OFDM symbol, i.e., one REG includes resources corresponding to one symbol in the time domain and one RB in the frequency domain. The resources that the PDCCH may occupy and the resources that the PDCCH actually occupies may be described by CCEs.

The main parameter configuration of the search space is described below in conjunction with tables 2 to 3.

TABLE 2

Among them, table 3 below illustrates that there are many types of SearchSpace:

TABLE 3 Table 3

Further explanation is made regarding PDCCH candidate. After the terminal device determines the candidate time-frequency position of the PDCCH according to the SearchSpace and CORESET configuration, the UE does not know on which CCE the PDCCH specific body will be transmitted, so that sequential blind detection is required. PDCCH candidate is the position that may contain the UE PDCCH within these candidate time-frequency positions. In order to reduce the number of blind tests of the UE, the network (network) may place these PDCCHs according to some rules, and the terminal device may reduce the number of blind tests according to some rules.

(9) Relationship between demodulation reference signal DMRS and downlink signal

In the downlink transmission process, the demodulation reference signal may be divided into a demodulation reference signal associated with a downlink control channel and a demodulation reference signal associated with a downlink data channel. In the embodiment of the application, the first demodulation reference signal is used for representing the demodulation reference signal associated with the downlink control channel, and the second demodulation reference signal is used for representing the demodulation signal associated with the downlink data channel.

The first demodulation reference signal and the downlink control channel are transmitted in the same mode, and the second demodulation reference signal and the downlink control channel are transmitted in the same mode.

Taking the downlink control channel as an example of PDCCH, the first demodulation reference signal may be DMRS associated with the PDCCH, or simply referred to as PDCCH DMRS. As shown in fig. 2 (a), PDCCH DMRS is distributed in one REG, it can be seen that the REG includes 12 Resource Elements (REs), the density of PDCCH DMRS is fixed to 1/4, and starts from the second RE of one REG in time. For a DMRS associated with a PDCCH, a channel experienced by a PDCCH symbol on a certain antenna port may be derived from a channel experienced by the DMRS symbol on the same antenna port, where the DMRS symbol associated with the PDCCH and the PDCCH symbol are using the same precoded transmission resource, or the DMRS symbol associated with the PDCCH and the PDCCH symbol are in the same frequency resource, the same OFDM symbol (slot), the same precoding group (precoding resource block group, PRG). It is appreciated that the frequency domain precoding granularity of PDCCH, PDCCH DMRS may be consistent with the precoding granularity of CORESET in which it resides.

Taking the downlink control channel as the PDSCH as an example, the second demodulation reference signal may be a DMRS associated with the PDSCH, or simply referred to as PDSCH DMRS. As illustrated in fig. 2 (b), the configuration type 1 (configuration type 1) is adopted, and PDSCH DMRS is distributed in one RB, it can be seen that the RB includes 12 Resource Elements (REs), the density of PDSCH DMRS is fixed to 1/2, and starts from the first RE of one REG in time. As also illustrated in fig. 2 (c), the allocation type2 (configuration type) is adopted, PDSCH DMRS is distributed in one RB, and it can be seen that the RB includes 12 Resource Elements (REs), the density of PDSCH DMRS is fixed to 2/6, and two REs are consecutive in time from the first RE of one REG. For a DMRS associated with PDSCH, a channel experienced by a PDSCH symbol on a certain antenna port may be derived from the channel experienced by the DMRS symbol on the same antenna port, where the DMRS symbol and PDSCH symbol associated with PDSCH are in the same frequency resource, the same time slot, the same precoding block group (precoding resource block group, PRG).

Note that PDCCH DMRS shown in fig. 2 (a), PDSCH DMRS shown in fig. 2 (b), and PDSCH DMRS shown in fig. 2 (c) are mainly different in distribution positions of the distinction PDCCH DMRS and PDSCH DMRS, and the same pattern is shown for the three parts PDCCH DMRS/PDSCH DMRS, but this is merely an example, and is not meant to limit the precoding of the three parts to be the same.

In addition, for PDSCH DMRS corresponding to the downlink broadcast/multicast/initial access procedure message (PBCH, SIB1, paging message, message 2, message 4, other system message, RRC configuration message, etc.), configuration type 1 (configuration type 1) is mainly adopted, and for downlink messages other than SIB1 (e.g., message 2, message 4, paging message, other system message, RRC configuration message, etc.), PDSCH DMRS may be configured to configuration type 2 (configuration type 2). These downstream messages will be described later.

Currently, the network device independently transmits PDCCH and PDCCH DMRS in a channel of a certain antenna port, and PDSCH and PDSCH DMRS in a channel of another certain antenna port. The terminal device demodulates the PDCCH through PDCCH DMRS, then acquires PDSCH, PDSCH DMRS based on the demodulated PDCCH, and demodulates PDSCH through PDSCH DMRS. The network device independently transmits PDCCH DMRS and PDSCH DMRS, occupies resource elements, but the occupied resource elements cannot bear bit information of an upper layer, so that transmission resources are consumed, and the cost is high. Based on this, the embodiment of the present application provides a downlink signal transmission method, by setting PDSCH DMRS and PDCCH DMRS to be multiplexed, PDCCH DMRS can be used for demodulation of PDSCH, so as to reduce the resources occupied by transmission PDSCH DMRS, and reduce the consumption of transmission resources and related overhead.

The method for transmitting the downlink signal provided by the embodiment of the application can be applied to a communication system architecture as shown in fig. 3, wherein the communication system comprises network equipment and terminal equipment.

The network device configures a first demodulation reference signal to be used for demodulating the downlink control channel and the downlink data channel. The terminal device may demodulate a downlink control channel and a downlink data channel according to the first demodulation reference signal when receiving the downlink control channel from the network device and receiving (acquiring) the downlink data channel from the network device based on the downlink control channel; or, the terminal device may first receive the downlink control channel from the network device, i.e. first demodulate the downlink control channel according to the first demodulation reference signal, then receive (acquire) the downlink data channel from the network device based on the control information in the downlink control channel, and demodulate the downlink data channel according to the first demodulation reference signal.

In addition, the network device may also indicate to the terminal device a transmission manner related to the downlink data channel, for example, transmission resources, precoding granularity, and so on. The terminal device may demodulate part or all of the downlink data channel according to the first demodulation reference signal in combination with the indication of the network device.

The following describes a scenario in which the embodiments of the present application are applicable. Referring to fig. 4, taking an interaction flow of information transmission between a network device and a terminal device in 5G NR as an example, downlink transmission related to an embodiment of the present application includes a process in which the network device sends a downlink message to the terminal device, where the downlink message transmission relates to a PDCCH and a PDSCH, for example, PBCH, SIB1, paging message, message 2, message 4, other system messages, radio resource control (Radio resource control, RRC) configuration message, and the RRC configuration message includes (for example, RRC Reconfiguration, RRC Connection Reconfiguration, etc. where the PDCCH is responsible for transmitting scheduling and configuration information related to the PDSCH, for example, indicated by DCI.

The specific interaction flow for transmitting information between the network device and the terminal device is as follows:

p100: the network device (or base station) transmits a synchronization signal at a specific location. In NR, the synchronization signal sent by the network device is called a synchronization/broadcast signal block (synchronization signal/Physical broadcast channel block, abbreviated as SS/PBCH block, abbreviated as SSB), and the SS/PBCH block is periodically sent by the network device. The content carried by the physical broadcast channel is referred to as a master system information block (master information block, MIB) in which the search space (i.e., searchSpaceZero) and control resource set (i.e., control resource zero) of SIB1 are indicated.

After the UE (terminal/User equipment) is powered on or when the UE needs to re-access the network, the UE scans the synchronization signal of the network device to perform downlink time and frequency synchronization, and receives configuration information about random access resources in the system information.

P101: the network device transmits system information (broadcast mode transmission) at a specific location, and signals carrying the system information are also called system information blocks (system information block, SIBs). Especially, the system information block No. 1 (SIB 1) carries information such as PDCCH search space (SearchSpace 1) including random access configuration information and message 2/message 4.

P101b: the network device periodically transmits paging information in a paging time window, and the terminal in an idle state periodically monitors the paging information, i.e. searches for a PDCCH corresponding to the paging information, wherein the PDCCH is scrambled by a paging-radio network temporary identifier (paging radio network temporary identifier, P-RNTI). The load of paging information is carried by the PDSCH, and the corresponding PDCCH indicates the time-frequency position where the PDSCH is located.

P102: the terminal selects a random access resource associated with the SSB according to the random access resource configuration information and the synchronized SSB, wherein the resource comprises a time resource, a frequency resource, a code domain resource (random access preamble), and sends a random access signal, also called message 1 (Msg 1), by using the random access resource. In NR, the association between SSB and random access resources enables the network device to acquire the downlink beam of the transmission message 2 and/or after detecting the random access preamble. Accordingly, the network device may attempt to receive the random access preamble.

P103: after receiving the message 1 sent by the UE, the network device estimates the timing advance of the UE according to the preamble sent by the user, and replies a message 2 (Msg 2) to the user, where the message 2 includes configuration information such as a time-frequency resource location, a modulation coding mode, and the like, where the UE is used to send the message 3 (Msg 3) for resolving the conflict. The random access response (random access response, RAR) may be referred to as message 2 at both the physical layer and the medium access layer (medium access control, MAC). But is also generally referred to as a response message corresponding to a specific certain random access preamble (e.g., transmitted by a terminal) at the physical layer; in the MAC layer, all random access preamble response messages detected by the network device are grouped in the form of MAC data units for a certain random access opportunity or random access opportunities. After the terminal has sent the random access preamble message 1, it will try to detect the message 2 within the random access response time window. Note that here the PDCCH search space corresponding to message 4 in message 2 or P105, i.e., the SearchSpace1 mentioned in P101. If there is no configuration in P101, then the search space/control resource set is the same as for SIB1 in P100.

P104: after receiving the message 2, the UE sends the message 3 on the corresponding time-frequency resource according to the configuration in the message 2.

P105: after receiving the message 3, the network device replies a message 4 (Msg 4) to the user, indicating that the terminal device has successfully accessed.

The communication system and the application scenario described in the embodiments of the present application are for more clearly describing the technical solution of the embodiments of the present application, and do not constitute a limitation on the technical solution provided by the embodiments of the present application.

The plural references in the embodiments of the present application refer to two or more. "and/or", describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate: the presence of a is shown, along with the presence of a and B, showing the presence of B. The character "/" generally indicates that the context-dependent object is an "or" relationship. In addition, it should be understood that although the terms first, second, etc. may be used in describing various objects in embodiments of the application, these objects should not be limited to these terms. These terms are only used to distinguish one object from another.

The terms "comprising" and "having" and any variations thereof, as used in the description of embodiments of the application, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed but may optionally include other steps or elements not listed or inherent to such process, method, article, or apparatus. It should be noted that, in the embodiments of the present application, words such as "exemplary" or "such as" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "e.g." in an embodiment should not be taken as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete fashion.

The method for transmitting the downlink signal and the interaction process between the network equipment and the terminal equipment involved in different methods provided by the embodiment of the application are described in detail below.

The method comprises the following steps: setting, in a predefined manner, one or more of the following conditions are met: the downlink control channel and the downlink data channel adopt the same transmission mode; the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the downlink data channel adopt the same transmission mode; and if the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode, the first demodulation reference signal can be used for demodulating the downlink control channel and the downlink data channel.

Wherein, adopting the same transmission mode includes adopting the same transmission resource (which may be partially the same), the same precoding, and the same precoding granularity. Furthermore, the use of the same transmission resources can also be understood as: with the same time and frequency, time may refer to any of the following: time slots, or bundles of multiple time slots; the frequency may refer to any one of the following: resource blocks, resource block groups; the use of the same precoding and the same precoding granularity can also be understood as: the same set of pre-coded resource blocks is employed. The same transmission mode may also indicate the same transmit beam (antenna port) is used. When the transmission resource portions are the same, the first demodulation reference signal may be used to demodulate the downlink control channel and the downlink data channel on the same transmission resource. For example, the downlink control channel is PDCCH, and the first demodulation reference signal is PDCCH DMRS; the downlink data channel is PDSCH, the second demodulation reference signal is PDSCH DMRS, and DMRS or PDCCH DMRS at the CORESET position where the PDCCH is located may be predefined and may be used to demodulate the PDCCH and PDSCH, where the first condition needs to be satisfied. Or the channel that the PDSCH symbol on a certain antenna port experiences may be predefined for PDSCH DMRS and its associated PDSCH, and the PDCCH scheduling the PDSCH, and may be deduced from the channel that the PDCCH scheduling the PDSCH (or the CORESET where the PDCCH is located) is associated with the DMRS and/or from the channel that the PDCCH scheduling the PDSCH experiences, the first condition needs to be satisfied. The first condition includes at least one of: (1) PDSCH DMRS symbols and PDSCH symbols are in the same (frequency) resource, the same slot, the same precoding resource block group. (2) PDSCH symbols and PDCCH DMRS (or DMRS in CORESET where PDCCH is located) symbols are in the same (frequency) resource, the same slot, the same precoding resource block group. (3) The PDSCH symbols and PDCCH (or core where PDCCH is located) symbols are in the same (frequency) resource, the same slot, the same precoding resource block group. (4) The antenna port of PDSCH has a correspondence with the antenna port of PDCCH DMRS (or DMRS in CORESET where PDCCH is located). (5) The antenna port of the PDSCH has a correspondence relationship with the antenna port of the PDCCH.

A flow chart of a downlink signal transmission method as illustrated in fig. 5 is shown, and the method includes the following steps:

s501a: the network device sends a first demodulation reference signal and a downlink control channel to the terminal device. The first demodulation reference signal is used for demodulating a downlink control channel and a downlink data channel scheduled by the downlink control channel.

And S501b, the network equipment transmits a downlink data channel scheduled by a downlink control channel to the terminal equipment. It should be noted that S501a and S501b do not distinguish between the sequence.

S502: the terminal equipment acquires a downlink control channel and a first demodulation reference signal, and demodulates the downlink control channel through the first demodulation reference signal.

S503: the terminal equipment acquires a downlink data channel based on the demodulated downlink control channel, and demodulates the downlink data channel according to the first demodulation reference signal.

In the embodiment of the application, by setting the downlink data channel to be the same as the downlink control channel for scheduling the downlink data channel and the demodulation reference signal transmission mode related to the downlink control channel, the demodulation reference signal related to the downlink control channel can be used for demodulating the downlink data channel, so that the network equipment does not need to send the demodulation reference signal related to the downlink data channel to the terminal equipment, the occupation of transmission resources is reduced, the DMRS overhead is reduced, and the demodulation (detection) complexity is reduced.

The second method is as follows: the network device adopts the same transmission mode to send a downlink control channel, a first demodulation reference signal and a downlink data channel, and sends first indication information to the terminal device, wherein the first indication information is used for indicating one or more of the following: (1) The downlink control channel and the downlink data channel adopt the same transmission mode. (2) And the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode. (3) The first demodulation reference signal and the downlink data channel adopt the same transmission mode. (4) The first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode. The terminal device may determine, according to the first indication information, that the first demodulation reference signal is available for demodulating the downlink control channel and the downlink data channel.

Optionally, the network device may send the first indication information before sending the first demodulation reference signal and/or the downlink control channel to the terminal device; or, the network device may also use the downlink control channel to carry the first indication information, and send the first indication information to the terminal device in a manner that the downlink control channel carries the first indication information. For example, taking the downlink control channel as an example of PDCCH, the DCI may specifically carry first indication information, which may specifically be a field defined in the DCI.

In summary, referring to a flow chart of a downlink signal transmission method illustrated in fig. 6, the method includes the following steps:

s601a: the network device sends a first demodulation reference signal and a downlink control channel to the terminal device. The first demodulation reference signal is used for demodulating a downlink control channel and a downlink data channel scheduled by the downlink control channel, wherein the downlink control channel carries the first indication information.

And S601b, the network equipment transmits a downlink data channel scheduled by a downlink control channel to the terminal equipment. It should be noted that S501a and S501b do not distinguish between the sequence.

S602: the terminal equipment acquires a downlink control channel and a first demodulation reference signal, demodulates the downlink control channel through the first demodulation reference signal, acquires first indication information, and determines that the first demodulation reference signal can be used for demodulating the downlink control channel and the downlink data channel based on the first indication information.

S603: the terminal equipment acquires a downlink data channel based on the demodulated downlink control channel, and demodulates the downlink data channel according to the first demodulation reference signal.

In the embodiment of the application, the network equipment adopts the same transmission mode to transmit the demodulation reference signals associated with the downlink control channel and the downlink control channel for scheduling the downlink data channel, and indicates the same related transmission mode to the terminal equipment. So that both communication parties can know that the demodulation reference signals associated with the downlink control channels can be used for demodulating the downlink data channels. The network device does not need to send demodulation reference signals associated with the downlink data channels to the terminal device, so that occupation of transmission resources is reduced, DMRS overhead is reduced, and demodulation (detection) complexity is reduced.

And a third method: based on the first or second method, the network device may further transmit a second demodulation reference signal associated with the downlink data channel. The terminal device may demodulate the downlink data channel according to method one or method two, and may demodulate the downlink data channel through the second demodulation reference signal. The terminal equipment demodulates the downlink data channel by combining the first demodulation reference signal and the second demodulation reference signal, so that the detection performance of the downlink data channel can be improved.

In an alternative embodiment, the network device may directly indicate to the terminal device the transmission resource occupied by the second demodulation reference signal, for example, the network device sends second indication information to the terminal device, where the second indication information is used to indicate whether one or more of the second demodulation reference signal, the number of the second demodulation reference signals, the time domain resource location and/or the frequency domain resource location of the second demodulation reference signal exist in the transmission resource except the time domain location occupied by the downlink control channel. The transmission resource indicates the same transmission resource used by the second demodulation reference signal, the first demodulation reference signal, the downlink control channel, and the downlink data channel, and the definition of the transmission resource can be understood by referring to the first method, which is not described in detail in the embodiment of the present application.

In another alternative embodiment, the network device may indicate to the terminal device, in an implicit indirect manner, the transmission resources occupied by the second demodulation reference signal. For example, the network device sends second indication information to the terminal device, where the second indication information includes information for indicating the first time domain offset, so as to implement indication of the time domain resource location of the second demodulation reference signal. The first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel (for example, a time domain resource starting position of the downlink control channel or a time domain resource ending position of the downlink control channel), or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel (or a time domain resource ending position).

Based on the embodiment, the time domain position of the second demodulation reference signal can be adjusted for different channel conditions, so that the channels are more matched, and the demodulation performance is better. For example, in a scene with higher mobility, the time variation of the channel is larger, so that the distance between the second demodulation reference signal and the first demodulation reference signal is slightly larger, and the estimated channel is more accurate and the demodulation performance is better.

Optionally, the network device may send the aforementioned second indication information before sending the first demodulation reference signal and/or the downlink control channel to the terminal device; or, the network device may also use the downlink control channel to carry the second indication information, and send the second indication information to the terminal device in a manner that the downlink control channel carries the second indication information. For example, taking the downlink control channel as an example of PDCCH, the DCI may specifically carry second indication information, which may specifically be a field defined in the DCI. On the basis of the second method, the first indication information and the second indication information may be carried in DCI and transmitted together, or may be carried in other messages (e.g., RRC messages) and transmitted together to the terminal device. The second instruction information and the first instruction information may be regarded as one piece or may be combined into one piece, and the information may indicate the content indicated by the first instruction information or the content indicated by the second instruction information.

Referring to fig. 7, a flow chart of a downlink signal transmission method is shown, and the method includes the following steps:

S701a: the network device sends a first demodulation reference signal and a downlink control channel to the terminal device. The first demodulation reference signal is used for demodulating a downlink control channel and a downlink data channel scheduled by the downlink control channel. Optionally, the downlink control channel carries the first indication information and/or the second indication information.

And S701b, the network equipment transmits the downlink data channel scheduled by the downlink control channel and a second demodulation reference signal associated with the downlink data channel to the terminal equipment. It should be noted that S501a and S501b do not distinguish between the sequence.

S702: the terminal equipment acquires a downlink control channel and a first demodulation reference signal, and demodulates the downlink control channel through the first demodulation reference signal. Optionally, the terminal device may further acquire the first indication information and/or the second indication information, and determine that the first demodulation reference signal is available for demodulating the downlink control channel and the downlink data channel based on the first indication information and/or the second indication information.

S703: the terminal equipment acquires a downlink data channel and a second demodulation reference signal based on the demodulated downlink control channel, and demodulates the downlink data channel according to the first demodulation reference signal and the second demodulation reference signal.

Taking the downlink control channel as PDCCH, the first demodulation reference signal is PDCCH DMRS, the downlink data channel is PDSCH, and the second demodulation reference signal is PDSCH DMRS as an example. Referring to a schematic diagram of demodulation reference signal distribution shown in fig. 8a, it is shown that the transmission manner of the PDSCH is the same as that of the PDCCH (or CORESET where the PDSCH is located), and in the case that PDSCH DMRS does not exist in the non-PDCCH position in the timeslot where the PDSCH is located, that is, the second indication information may be used to indicate that PDSCH DMRS does not exist in the non-PDCCH position in the timeslot where the PDSCH is located in the same transmission resource. The terminal device receives the second indication information and may demodulate the PDSCH according to PDCCH DMRS transmitted by the network device.

Taking the downlink control channel as PDCCH, the first demodulation reference signal is PDCCH DMRS, the downlink data channel is PDSCH, and the second demodulation reference signal is PDSCH DMRS as an example. Referring to fig. 8b, the transmission mode of PDSCH is the same as that of PDCCH (or CORESET where PDCCH is located), PDSCH DMRS is present in the non-PDCCH position in the slot where PDSCH is located, and the interval between PDSCH DMRS and PDCCH DMRS (or CORESET where PDCCH is located) is K3 OFDM symbols. K3 OFDM's are the first time domain offset. The second indication information may include K3, so that the network device sends the second indication information to indicate that the network device sends PDSCH DMRS in an implicit manner through indicating the time domain resource position of PDSCH DMRS relative to the time domain position of the PDCCH, so that the terminal device knows that the PDSCH can be demodulated according to PDCCH DMRS and PDSCH DMRS sent by the network device, and the detection performance of the PDSCH is improved. In which case k3=7 is specifically illustrated in fig. 8 b. However, it should be noted that, the value of K3 is not limited in the embodiment of the present application, and the first time domain offset may be represented on OFDM and represented by K3 OFDM; the first time domain shift amount may also be an offset over a time slot or the like.

It should be appreciated that in the present application (e.g., method one, method two, or method three), the bandwidth of the downlink data channel may be less than the bandwidth of the downlink control channel (or CORESET where the downlink control channel is located). Further, the frequency resource block location (or the set of indexes of the resource blocks) where the downlink data channel is located belongs to a subset of the frequency resource block locations of the downlink control channel (or the CORESET where the downlink control channel is located).

The method four: the network equipment sends a downlink control channel, a first demodulation reference signal and a downlink data channel to the terminal equipment, and sends third indication information to the terminal equipment, wherein the third indication information is used for indicating one or more of precoding granularity of the downlink control channel, precoding granularity of the first demodulation reference signal, precoding granularity of the downlink data channel and precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel. The terminal device may demodulate part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signal.

Optionally, the network device may send the third indication information before sending the first demodulation reference signal and/or the downlink control channel; or, the network device may also use the downlink control channel to carry the third indication information, and send the third indication information to the terminal device in a manner that the downlink control channel carries the third indication information. For example, taking the downlink control channel as an example of PDCCH, the DCI may specifically carry third indication information, and the first indication information may specifically be a field defined in the DCI.

Optionally, the terminal device may demodulate part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signal, and may be implemented with reference to the following manner: firstly, the terminal device may determine a transmission mode of the downlink data channel or a transmission mode of a second demodulation reference signal according to third indication information and the downlink control channel demodulated by the first demodulation reference signal, where the transmission mode includes one or more of precoding, precoding granularity, and transmission resources. Further, the terminal device determines whether the transmission mode of the downlink control channel (or the first demodulation reference signal) is the same as the transmission mode of the downlink data channel (or the second demodulation reference signal), and when the transmission modes are the same, the terminal device can demodulate a part of the downlink data channel sent by the network device according to the first demodulation reference signal; when all the data channels are the same, the terminal device may demodulate all the downlink data channels sent by the network device according to the first demodulation reference signal.

In the following, how the terminal device determines the transmission mode of the downlink data channel or the transmission mode of the second demodulation reference signal in different situations indicated by the third indication information sent by the network device is described in detail.

First case: the following association relationship is known between the network device and the terminal device by adopting a predefined mode: the precoding granularity of the downlink control channel is related to the precoding granularity of the downlink data channel; or, the precoding granularity of the downlink control channel is related to the precoding granularity of the second demodulation reference signal; or, the precoding granularity of the first demodulation reference signal is related to the precoding granularity of the downlink data channel; alternatively, the precoding granularity of the first demodulation reference signal is correlated with the precoding granularity of the second demodulation reference signal. And the first demodulation reference signal and the downlink control channel adopt the same precoding granularity, and the second demodulation reference signal and the downlink data channel adopt the same precoding granularity. For example, PDCCH DMRS is the same as the precoding granularity of the PDCCH, the precoding granularity of the PDCCH is K1 REGs, and K1 can be any one of values 2, 3, 4, 6 and bandwidth; PDSCH DMRS is the same as the precoding granularity of PDSCH, and the precoding granularity of PDSCH is K2 RBs (REG), where K2 may take any one of values 2 and 4. When the precoding granularity of the PDCCH may be predefined to be 2 REGs, the precoding granularity of the PDSCH is 2 RBs; when the precoding granularity of the PDCCH is 4 REGs, the precoding granularity of the PDSCH is 4 RBs; when the precoding granularity of the PDCCH is 3 REGs, the precoding granularity of the PDSCH is 2 RBs; when the precoding granularity of the PDCCH is 6 REGs, the precoding granularity of the PDSCH is 3 RBs.

The third indication information sent by the network device indicates any one of the precoding granularity of the downlink control channel and the precoding granularity of the first demodulation reference signal, and the terminal device can determine other precoding granularity not indicated by the network device based on the known association relation and the third indication information. For example, the third indication information sent by the network device indicates the precoding granularity of the downlink control channel, and the terminal device may determine the precoding granularity of the downlink data channel related to the third indication information, the precoding granularity of the second demodulation reference signal, and the precoding granularity of the first demodulation reference signal.

Taking the transmission mode of the downlink data channel determined by the terminal device as an example, if the precoding granularity of the downlink data channel obtained by the terminal device is the same as that of the first demodulation reference signal, the terminal device determines that the downlink data channel and the first demodulation reference signal adopt the same precoding resource block group, and the terminal device can demodulate all downlink data channels sent by the network device according to the first demodulation reference signal or demodulate downlink data channels sent by the network device and having the same frequency position (or called frequency domain resource) as the first demodulation reference signal according to the first demodulation reference signal. For example, as shown in fig. 9a, the vertical direction represents the time domain dimension, the horizontal direction represents the frequency domain dimension, PDCCH and PDCCH DMRS are located in OFDM symbol No. 0, PDSCH and PDSCH DMRS start from OFDM symbol No. 1 (the number of sustained OFDM symbols is not limited). The precoding granularity of the PDCCH is K1 REG, and K1 is 2; the precoding granularity of PDSCH is K2 REGs (or RBs), with K2 being 2. The precoding resource block group of PDCCH and the precoding resource block group of PDSCH at the same frequency location are the same, and as shown in fig. 9a, the same precoding is used for PDSCH PRG j and PDCCH precoding (precoding) REG group j, and the same precoding is used for PDSCH PRG j+1 and PDCCH precoding (precoding) REG group j+1, in the same pattern. The terminal device may demodulate all of PDSCH transmitted by the network device according to PDCCH DMRS, or demodulate a downlink data channel transmitted by the network device according to the first demodulation reference signal and having the same frequency position as the first demodulation reference signal.

Taking the transmission mode of the downlink data channel determined by the terminal device as an example, if the precoding granularity of the downlink data channel obtained by the terminal device is different from the precoding granularity of the first demodulation reference signal, and the terminal device determines that the downlink data channel is partially overlapped with the precoding resource block group adopted by the first demodulation reference signal, the terminal device can demodulate the downlink data channel in the overlapped part according to the first demodulation reference signal of the overlapped part.

For example, as shown in fig. 9b, the vertical represents the time domain dimension and the horizontal represents the frequency domain dimension. PDCCH and PDCCH DMRS are located in OFDM symbol No. 0, PDSCH and PDSCH DMRS start from OFDM symbol No. 1 (the number of persistent OFDM symbols is not limited). The precoding granularity of the PDCCH is K1 REG, and K1 is 3; the precoding granularity of PDSCH is K2 REGs (or RBs), with K2 being 2. The precoding resource block group of PDCCH and the precoding resource block group of PDSCH partially overlap, as illustrated in fig. 9b for PDSCH PRG j, PDCCH precoding (precoding) REG group j: the PDCCH precoding (precoding) REG group j includes PDSCH PRG j, and precoding of the overlapping portion, i.e., PDSCH PRG j, is the same as precoding of the PDCCH precoding (precoding) REG group j, and the precoding is indicated as the same in the same pattern in fig. 9 b. The terminal device may demodulate PDSCH in PDSCH PRG j according to PDCCH DMRS. In addition, for precoding of PDSCH prgj+1, precoding of PDSCH prgj+1 may be set to be the same as precoding of PDCCH corresponding to the position of the smallest RB in precoding of PDSCH prgj+1, and fig. 9b also illustrates: the precoding of PDSCH PRG j+1 is the same as the precoding of PDCCH precoding (precoding) REG group j. The terminal device may determine precoding of PDSCH prgj+1 based on the setting.

As also shown in fig. 9c, the vertical represents the time domain dimension and the horizontal represents the frequency domain dimension. PDCCH and PDCCH DMRS are located in OFDM symbol No. 0, PDSCH and PDSCH DMRS start from OFDM symbol No. 1 (the number of persistent OFDM symbols is not limited). The precoding granularity of the PDCCH is K1 REG, and K1 is 3; the precoding granularity of PDSCH is K2 REGs (RBs), with K2 being 2. The precoding resource block group of PDCCH and the precoding resource block group of PDSCH partially overlap, as illustrated by PDSCH PRG j, PDCCH precoding (precoding) REG group j in fig. 9 c. The PDCCH precoding (precoding) REG group j includes PDSCH PRG j, and precoding of the PDSCH PRG j, which is a superposition of the PDCCH precoding (precoding) REG group j, is the same as precoding of the PDCCH precoding (precoding) REG group j, and the precoding is indicated by the same pattern in fig. 9 c. The terminal device may demodulate PDSCH in PDSCH PRG j according to PDCCH DMRS. In addition, for precoding of PDSCH prgj+1, precoding of PDSCH prgj+1 may be set to be the same as precoding of PDCCH corresponding to the position of the largest RB in precoding of PDSCH prgj+1, and fig. 9c also illustrates: the precoding of PDSCH prgj+1 is the same as the precoding of PDCCH precoding (precoding) REG group j+1, and the terminal device may determine the precoding of PDSCH prgj+1 based on the setting.

As also shown in fig. 9d, the vertical represents the time domain dimension and the horizontal represents the frequency domain dimension. PDCCH and PDCCH DMRS are located in OFDM symbol No. 0, PDSCH and PDSCH DMRS start from OFDM symbol No. 1 (the number of persistent OFDM symbols is not limited). The precoding granularity of the PDCCH is K1 REG, and K1 is 3; the precoding granularity of PDSCH is K2 REGs (RBs), with K2 being 2. The precoding resource block group of PDCCH and the precoding resource block group of PDSCH partially overlap, as illustrated by PDSCH PRG j, PDCCH precoding (precoding) REG group j in fig. 9 d. The PDCCH precoding (precoding) REG group j includes PDSCH PRG j, and precoding of the PDSCH PRG j, which is a superposition of the PDCCH precoding (precoding) REG group j, is the same as precoding of the PDCCH precoding (precoding) REG group j, and the precoding is indicated as the same in the same pattern in fig. 9 d. The terminal device may demodulate PDSCH in PDSCH PRG j according to PDCCH DMRS. In addition, precoding for PDSCH prgj+1 is not set, and the network device side can transmit at will.

In another implementation, the precoding resource block group of the PDCCH and the precoding resource block group of the PDSCH have partially overlapped precoding, and the terminal device may determine the precoding of the non-overlapped portion according to the overlapped portion precoding. For example, in fig. 9d, PDSCH PRG j partially coincides with PDCCH REG group j, i.e., PDSCH PRG j. The terminal device may determine the precoding P1 of PDSCH prgj+1 from the precoding P0 of PDCCH REG group j (or the precoding P0 of PDSCH prgj), denoted p1=pxp0; wherein P is a pre-defined or pre-configured vector determined according to pre-configured information; for example, the number of the cells to be processed, By the method, the indication overhead of PDSCH precoding can be reduced, and simultaneously, the diversity of the PDSCH is increased through more flexible precoding, so that the transmission performance is improved.

It should be appreciated that in the present application (e.g., method four), the bandwidth of the downlink data channel may be different from the bandwidth of the downlink control channel (or CORESET where the downlink control channel is located). Further, the frequency resource block location (or the set of indexes of the resource blocks) where the downlink data channel is located may be the same as only a part of the frequency resource block location of the downlink control channel (or the core where the downlink control channel is located).

Second case: and setting a default precoding granularity of the second demodulation reference signal or the downlink data channel in a predefined mode. Wherein the second demodulation reference signal and the downlink data channel adopt the same precoding granularity. For example, in NR, the precoding granularity of PDSCH corresponding to a downlink broadcast/multicast/initial access procedure message (PBCH, SIB1, paging message, message 2, other system message, message 4, RRC configuration message, etc.), defaults to 2 RBs.

The third indication information sent by the network device indicates any one of the precoding granularity of the downlink control channel and the precoding granularity of the first demodulation reference signal. The precoding granularity of the downlink control channel is the same as that of the first demodulation reference signal. For example, in NR, the precoding granularity of PDCCH (or PDCCH DMRS) is the same as the CORESET precoding granularity where it is located, the CORESET precoding granularity configured by the network device may be 2, 4, 6 REGs, or the entire CORESET bandwidth, configured by the base station in SIB 1. In addition, in NR, the terminal device may also assume that the CORESET precoding granularity corresponding to paging message, message 2, and message 4 is identical to the SIB1CORESET precoding granularity, or may be configured in SIB1 by the base station. The terminal device may determine a precoding granularity of the downlink data channel and the second demodulation reference signal, and a precoding granularity of the downlink control channel and the first demodulation reference signal based on the third indication information and the default precoding granularity. And the terminal device demodulates part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signal, which is not described in detail in the embodiment of the present application.

Third case: the third indication information sent by the network device indicates any one of the precoding granularity of the downlink control channel and the precoding granularity of the first demodulation reference signal, and any one of the precoding granularity of the downlink data channel and the precoding granularity of the second demodulation reference signal. The precoding granularity of the downlink control channel is the same as that of the first demodulation reference signal; the precoding granularity of the downlink data channel is the same as the precoding granularity of the second demodulation reference signal. The terminal device may determine a precoding granularity of the downlink data channel and the second demodulation reference signal, a precoding granularity of the downlink control channel and the first demodulation reference signal based on the third indication information. And the terminal device demodulates part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signal, which is not described in detail in the embodiment of the present application.

In response to the above three situations, referring to fig. 10, an embodiment of the present application provides a flow chart of a downlink signal transmission method, where the method includes the following steps:

S1001a: the network device sends a first demodulation reference signal and a downlink control channel to the terminal device. The first demodulation reference signal is used for demodulating a downlink control channel and a downlink data channel scheduled by the downlink control channel. Optionally, the downlink control channel carries the third indication information, and in different cases, the specific indication content of the third indication information is different, which can be understood by referring to the above three cases, and specific illustration of the third indication information is not shown in fig. 10.

And S1001b, the network equipment sends a downlink data channel scheduled by a downlink control channel to the terminal equipment. It should be noted that S501a and S501b do not distinguish between the sequence.

S1002: the terminal equipment acquires a downlink control channel and a first demodulation reference signal, and demodulates the downlink control channel through the first demodulation reference signal. Optionally, the terminal device may further obtain third indication information.

S1003: the terminal equipment acquires a downlink data channel based on the demodulated downlink control channel, and demodulates part or all of the downlink data channel sent by the network equipment according to the first demodulation reference signal and the third indication information.

And a fifth method: based on the fourth method, the network device may further send a second demodulation reference signal associated with the downlink data channel. The terminal device may demodulate the downlink data channel according to the fourth method, and may also demodulate the downlink data channel through the second demodulation reference signal. The terminal equipment demodulates the downlink data channel by combining the first demodulation reference signal and the second demodulation reference signal, so that the detection performance of the downlink data channel can be improved.

Referring to fig. 11, an embodiment of the present application provides a flow chart of a downlink signal transmission method, where the method includes the following steps:

s1101a: the network device sends a first demodulation reference signal and a downlink control channel to the terminal device. The first demodulation reference signal is used for demodulating a downlink control channel and a downlink data channel scheduled by the downlink control channel. Optionally, the downlink control channel carries the third indication information, and the content indicated by the third indication information may be implemented by referring to a fourth method, which is not described in detail in the embodiment of the present application.

And 1101b, the network device transmits the downlink data channel scheduled by the downlink control channel and the second demodulation reference signal associated with the downlink data channel to the terminal device. It should be noted that S501a and S501b do not distinguish between the sequence.

S1102: the terminal equipment acquires a downlink control channel and a first demodulation reference signal, and demodulates the downlink control channel through the first demodulation reference signal. Optionally, the terminal device may further obtain third indication information.

S1103: the terminal equipment acquires a downlink data channel and a second demodulation reference signal based on the demodulated downlink control channel, and demodulates the downlink data channel sent by the network equipment according to the first demodulation reference signal and the second demodulation reference signal.

Based on the same concept, referring to fig. 12, an embodiment of the present application provides a downlink signal transmission apparatus 1200, where the apparatus 1200 includes a processing module 1201 and a communication module 1202. The communication apparatus 1200 may be a network device, or may be an apparatus that is applied to a network device and is capable of supporting the network device to perform a method for transmitting a downlink signal, or the communication apparatus 1200 may be a terminal device, or may be an apparatus that is applied to a terminal device and is capable of supporting the terminal device to perform a method for transmitting a downlink signal.

The communication module may also be referred to as a transceiver module, a transceiver device, etc. The processing module may also be referred to as a processor, a processing board, a processing unit, a processing device, etc. Alternatively, the device for implementing the receiving function in the communication module may be regarded as a receiving unit, and it should be understood that the communication module is configured to perform the sending operation and the receiving operation on the network device side or the terminal device side in the foregoing method embodiment, and the device for implementing the sending function in the communication module is regarded as a sending unit, that is, the communication module includes the receiving unit and the sending unit. When the apparatus 1200 is applied to a network device, the communication module 1202 includes a receiving unit for performing a receiving operation on the network device side, for example, receiving an uplink signal (uplink control channel/uplink data channel) from a terminal device; the communication module 1202 includes a transmitting unit for performing a transmitting operation on the network device side, for example, transmitting a downlink signal to the terminal device. When the apparatus 1200 is applied to a terminal device, the communication module 1202 includes a receiving unit for performing a receiving operation on the terminal device side, for example, receiving a downlink signal from a network device. The communication module 1202 includes a transmitting unit for performing a transmitting operation on the terminal device side, for example, transmitting an uplink signal to the network device. In addition, it should be noted that if the device is implemented by a chip/chip circuit, the communication module may be an input/output circuit and/or a communication interface, and perform an input operation (corresponding to the foregoing receiving operation) and an output operation (corresponding to the foregoing transmitting operation); the processing module is an integrated processor or microprocessor or integrated circuit.

An embodiment of the apparatus 1200 applied to a network device will be described in detail below. The apparatus 1200 includes:

the processing module 1201 is configured to generate a downlink control channel, a first demodulation reference signal, and a downlink data channel, where the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling the downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel.

A communication module 1202, configured to send the downlink control channel and the first demodulation reference signal to a terminal device.

The communication module 1202 is further configured to send the downlink data channel to the terminal device.

In the embodiment of the application, the demodulation reference signals associated with the downlink control channels can be used for demodulating the downlink data channels, multiplexing the demodulation reference signals is implemented, and the consumption of transmission resources and the signaling overhead are reduced.

In an alternative embodiment, the communication module 1202 is further configured to send first indication information to the terminal device, where the first indication information is used to indicate one or more of the following: the downlink control channel and the downlink data channel adopt the same transmission mode; the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.

In the embodiment of the application, the downlink data channel is set to be the same as the downlink control channel for scheduling the downlink data channel and the demodulation reference signal transmission mode related to the downlink control channel, so that the demodulation reference signal related to the downlink control channel can be used for demodulating the downlink data channel, and multiplexing of the demodulation reference signal is implemented. The network device informs the terminal device through the first indication information without issuing the demodulation reference signals associated with the downlink control channels, so that the consumption of transmission resources can be reduced, and the signaling overhead is reduced.

The following conditions are satisfied for one or more of: the downlink control channel and the downlink data channel adopt the same transmission mode; the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode. By setting the downlink data channel to be the same as the downlink control channel for scheduling the downlink data channel and the demodulation reference signal transmission mode associated with the downlink control channel, the demodulation reference signal associated with the downlink control channel can be used for demodulating the downlink data channel, so that multiplexing of the demodulation reference signal is realized.

In the application, the network equipment informs the terminal equipment through the first indication information, the downlink data channel is the same as the downlink control channel for scheduling the downlink data channel and the demodulation reference signal transmission mode related to the downlink control channel, multiplexing of the demodulation reference signal is implemented, and the terminal equipment can demodulate the downlink data channel according to the demodulation reference signal related to the downlink control channel. The network equipment is not required to issue demodulation reference signals associated with the downlink control channels, so that the consumption of transmission resources can be reduced, and the signaling overhead is reduced.

In an alternative embodiment, the same transmission mode includes the same transmission resource, the same precoding, and the same precoding granularity.

In an alternative embodiment, the communication module 1202 is further configured to send a second demodulation reference signal associated with the downlink data channel to the terminal device. In this way, the terminal device can demodulate the downlink data channel by combining the first demodulation reference signal and the second demodulation reference signal, so as to improve the detection performance of the downlink data channel.

In an alternative embodiment, the communication module 1202 is further configured to send second indication information to the terminal device, where the second indication information is used to indicate a time domain resource location and/or a frequency domain resource location occupied by the second demodulation reference signal.

In an alternative embodiment, the communication module 1202 is further configured to send second indication information to the terminal device, where the second indication information includes information indicating the first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel (for example, a time domain resource starting position of the downlink control channel or a time domain resource ending position of the downlink control channel), or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel (or a time domain resource ending position). In this way, the location of the time domain resource where the second demodulation reference signal is located can be indicated to the terminal device indirectly or implicitly, and the terminal device can know the location of the second demodulation reference signal based on the time domain resource location where the first demodulation reference signal/downlink control channel is located and combined with the first time domain offset.

In an optional implementation manner, the communication module 1202 is further configured to send third indication information to the terminal device, where the third indication information is used to indicate one or more of a precoding granularity of the downlink control channel, a precoding granularity of the first demodulation reference signal, a precoding granularity of the downlink data channel, and a precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel. In this way, the terminal device can demodulate part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signals, and implement multiplexing of the demodulation reference signals, so that transmission resources occupied by the second demodulation reference signals associated with the downlink data channels can be reduced, and signaling overhead can be reduced.

In an alternative embodiment, the precoding granularity of the downlink control channel is related to the precoding granularity of the downlink data channel; or, the precoding granularity of the downlink control channel is related to the precoding granularity of the second demodulation reference signal; or, the precoding granularity of the first demodulation reference signal is related to the precoding granularity of the downlink data channel; alternatively, the precoding granularity of the first demodulation reference signal is correlated with the precoding granularity of the second demodulation reference signal.

An embodiment of the apparatus 1200 applied to a terminal device will be described in detail below. The apparatus 1200 includes:

a communication module 1202, configured to receive a downlink control channel and a first demodulation reference signal from a network device, where the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling a downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel.

A processing module 1201 is configured to demodulate the downlink control channel according to the first demodulation reference signal.

The communication module 1202 is further configured to receive the downlink data channel from the network device.

The processing module 1201 is further configured to demodulate the downlink data channel according to the first demodulation reference signal.

In an alternative implementation, the communication module 1202 is specifically configured to receive a downlink control channel from a network device, and receive (acquire) the downlink data channel from the network device based on the downlink control channel; the processing module 1201 is specifically configured to demodulate a downlink control channel and a downlink data channel according to the first demodulation reference signal; alternatively, the communication module 1202 may first receive a downlink control channel from the network device, and the processing module 1201 first demodulates the downlink control channel according to the first demodulation reference signal; the communication module 1202 further receives (acquires) the downlink data channel from the network device based on the control information in the downlink control channel, and the processing module 1201 demodulates the downlink data channel according to the first demodulation reference signal.

In an alternative embodiment, the communication module 1202 is further configured to receive first indication information from the network device, where the first indication information is used to indicate one or more of the following: the downlink control channel and the downlink data channel adopt the same transmission mode; the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the downlink data channel adopt the same transmission mode; the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.

In an alternative embodiment, the communication module 1202 is further configured to receive a second demodulation reference signal associated with the downlink data channel from the network device; the processing module 1201 is further configured to demodulate the downlink data channel according to the first demodulation reference signal and the second demodulation reference signal. In this way, the terminal device can demodulate the downlink data channel by combining the first demodulation reference signal and the second demodulation reference signal, so as to improve the detection performance of the downlink data channel.

In an alternative embodiment, the communication module 1202 is further configured to send second indication information to the terminal device, where the second indication information is further used to indicate a time domain resource location and/or a frequency domain resource location occupied by the second demodulation reference signal.

In an alternative embodiment, the communication module 1202 is further configured to send second indication information to the terminal device,

the second indication information includes information for indicating a first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel (for example, a time domain resource starting position of the downlink control channel or a time domain resource ending position of the downlink control channel), or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or represents a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel (or a time domain resource ending position). In this way, the time domain resource position where the second demodulation reference signal is located can be indirectly or implicitly indicated to the terminal device, and the terminal device can know the position of the second demodulation reference signal based on the time domain resource position where the first demodulation reference signal/downlink control channel is located and combined with the first time domain offset.

In an optional embodiment, the communication module 1202 is further configured to receive third indication information from the network device, where the third indication information is used to indicate one or more of a precoding granularity of the downlink control channel, a precoding granularity of the first demodulation reference signal, a precoding granularity of the downlink data channel, and a precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel. In this way, the terminal device can demodulate part or all of the downlink data channels sent by the network device according to the third indication information and the first demodulation reference signals, and implement multiplexing of the demodulation reference signals, so that transmission resources occupied by the second demodulation reference signals associated with the downlink data channels can be reduced, and signaling overhead can be reduced.

In an optional embodiment, the processing module 1201 is further configured to demodulate part or all of the downlink data channels sent by the network device according to the first demodulation reference signal and the third indication information.

In an alternative embodiment, the processing module 1201 is specifically configured to: determining a transmission mode of the downlink data channel and a transmission mode of the first demodulation reference signal according to third indication information and the downlink control channel demodulated by the first demodulation reference signal; the downlink data channel and the second demodulation reference signal adopt the same transmission mode, the first demodulation reference signal and the downlink control channel adopt the same transmission mode, and the transmission mode comprises precoding, precoding granularity and transmission resources. If the transmission mode of the downlink data channel is the same as the transmission mode of the first demodulation reference signal, demodulating all of the downlink data channels according to the first demodulation reference signal; and if the transmission mode of the downlink data channel is partially the same as that of the first demodulation reference signal, demodulating the part in the downlink data channel according to the first demodulation reference signal.

In an alternative embodiment, the processing module 1201 is specifically configured to: and determining that the precoding granularity of the downlink data channel is the same as the precoding granularity of the first demodulation reference signal according to the third indication information. Demodulating all downlink data channels sent by the network equipment according to the first demodulation reference signal; or the terminal equipment demodulates a downlink data channel which is sent by the network equipment according to the first demodulation reference signal and occupies the same frequency domain resource with the first demodulation reference signal.

In an alternative embodiment, the processing module 1201 is specifically configured to: and according to the third indication information, determining that the precoding granularity of the downlink data channel is different from that of the first demodulation reference signal, and the precoding resource block group of the downlink data channel is partially overlapped with that of the first demodulation reference signal. Demodulating a downlink data channel in the pre-coding resource block group of the overlapping part according to a first demodulation reference signal in the pre-coding resource block group of the overlapping part.

Based on the same concept, as shown in fig. 13, an embodiment of the present application provides a communication apparatus 1300, which communication apparatus 1300 may be a chip or a chip system. Alternatively, the chip system in the embodiment of the present application may be formed by a chip, and may also include a chip and other discrete devices.

The communications apparatus 1300 can include at least one processor 1310, the processor 1310 coupled to a memory, which can optionally be located within the apparatus or external to the apparatus. For example, the communications apparatus 1300 can also include at least one memory 1320. Memory 1320 holds computer programs, configuration information, computer programs or instructions and/or data necessary to implement any of the embodiments described above; processor 1310 may execute a computer program stored in memory 1320 to perform the method of any of the embodiments described above.

The coupling in the embodiments of the present application is an indirect coupling or communication connection between devices, units, or modules, which may be in electrical, mechanical, or other forms for information interaction between the devices, units, or modules. Processor 1310 may operate in conjunction with memory 1320. The specific connection medium between the transceiver 1330, the processor 1310, and the memory 1320 is not limited in the embodiment of the present application.

A transceiver 1330 may also be included in the communications apparatus 1300, and the communications apparatus 1300 may interact with other devices via the transceiver 1330. The transceiver 1330 may be a circuit, a bus, a transceiver, or any other device that may be used to interact with information, or referred to as a signal transceiver unit. As shown in fig. 13, the transceiver 1330 includes a transmitter 1331, a receiver 1332, and an antenna 1333. In addition, when the communication device 1300 is a chip-type device or circuit, the transceiver in the device 1300 may be an input/output circuit and/or a communication interface, and may input data (or receive data) and output data (or transmit data), and the processor may be an integrated processor or a microprocessor or an integrated circuit, and the processor may determine the output data according to the input data.

In one possible implementation manner, the communication apparatus 1300 may be applied to a network device, and the specific communication apparatus 1300 may be a network device, or may be an apparatus capable of supporting a network device to implement a function of a network device in any of the foregoing embodiments. Memory 1320 stores the necessary computer programs, computer programs or instructions and/or data to implement the functions of the network devices in any of the embodiments described above. Processor 1310 may execute a computer program stored in memory 1320 to perform the method performed by the network device in any of the embodiments described above. For application to a network device, the transmitter 1331 in the communications apparatus 1300 can be configured to transmit transmission control configuration information to a terminal device via the antenna 1333 and the receiver 1332 can be configured to receive transmission information transmitted by the terminal device via the antenna 1333.

In another possible implementation manner, the communication apparatus 1300 may be applied to a terminal device, and the specific communication apparatus 1300 may be a terminal device, or may be an apparatus capable of supporting a terminal device to implement a function of a terminal device in any of the foregoing embodiments. Memory 1320 stores the necessary computer programs, computer programs or instructions and/or data to implement the functions of the terminal device in any of the embodiments described above. Processor 1310 may execute a computer program stored in memory 1320 to perform the method performed by the terminal device in any of the embodiments described above. For application to a terminal device, the receiver 1332 in the communications apparatus 1300 can be configured to receive transmission control configuration information transmitted by a network device via the antenna 1333 and the transmitter 1331 can be configured to transmit transmission information to the network device via the antenna 1333.

Since the communication apparatus 1300 provided in this embodiment may be applied to a network device, a method performed by the network device may be completed, or may be applied to a terminal device, a method performed by the terminal device may be completed. Therefore, reference may be made to the above method embodiments for the technical effects, which are not described herein.

In an embodiment of the present application, the processor may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and may implement or execute the methods, steps, and logic blocks disclosed in the embodiments of the present application. The general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present application may be embodied directly in a hardware processor for execution, or in a combination of hardware and software modules in the processor for execution.

In the embodiment of the present application, the memory may be a nonvolatile memory, such as a hard disk (HDD) or a Solid State Drive (SSD), or may be a volatile memory (RAM). The memory may also be any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited to such. The memory in embodiments of the present application may also be circuitry or any other device capable of implementing a memory function for storing a computer program, a computer program or instructions and/or data.

Based on the above embodiments, referring to fig. 14, an embodiment of the present application further provides another communication apparatus 1400, including: interface circuitry 1410 and a processor 1420; interface circuitry 1410 for receiving code instructions and transmitting to the processor; a processor 1420 configured to execute code instructions to perform the method performed by the network device or the method performed by the terminal device in any of the embodiments described above.

Since the communication apparatus 1400 provided in the present embodiment is applicable to a network device, a method performed by the network device described above is performed, or to a terminal device, a method performed by the terminal device is performed. Therefore, reference may be made to the above method embodiments for the technical effects, which are not described herein.

Based on the above embodiments, the embodiments of the present application further provide a communication system, where the communication system includes at least one communication device applied to a network device and at least one communication device applied to a terminal device. The technical effects obtained can be referred to the above method embodiments, and will not be described herein.

Based on the above embodiments, the embodiments of the present application also provide a computer readable storage medium storing a computer program or instructions that, when executed, cause a method performed by a network device or a method performed by a terminal device in any of the above embodiments to be performed. The computer readable storage medium may include: various media capable of storing program codes, such as a U disk, a mobile hard disk, a read-only memory, a random access memory, a magnetic disk or an optical disk.

In order to implement the functions of the communication device of fig. 12 to 14, the embodiment of the present application further provides a chip, which includes a processor, and is configured to support the communication device to implement the functions related to the network device or the terminal device in the method embodiment. In one possible design, the chip is connected to a memory or the chip comprises a memory for holding the necessary computer programs or instructions and data for the communication device.

It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer programs or instructions. These computer programs or instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer programs or instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer programs or instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present application without departing from the scope of the embodiments of the application. Thus, if such modifications and variations of the embodiments of the present application fall within the scope of the claims and the equivalents thereof, the present application is also intended to include such modifications and variations.

Claims

A method for transmitting a downlink signal, comprising:

the network equipment sends a downlink control channel and a first demodulation reference signal to the terminal equipment, wherein the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling a downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel;

and the network equipment sends the downlink data channel to the terminal equipment.
The method of claim 1, wherein one or more of the following conditions are satisfied:

the downlink control channel and the downlink data channel adopt the same transmission mode;

the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.
The method of claim 1, wherein the method further comprises:

the network device sends first indication information to the terminal device, wherein the first indication information is used for indicating one or more of the following:

The downlink control channel and the downlink data channel adopt the same transmission mode;

the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.
A method as claimed in claim 2 or 3, wherein the same transmission means comprises the same transmission resources, the same precoding and the same precoding granularity.
The method of any one of claims 2-4, wherein the method further comprises:

and the network equipment sends the second demodulation reference signal associated with the downlink data channel to the terminal equipment.
The method of claim 5, wherein the method further comprises:

the network device sends second indication information to the terminal device, wherein the second indication information is used for indicating the time domain resource position and/or the frequency domain resource position of the second demodulation reference signal.
The method of claim 5, wherein the method further comprises:

The network equipment sends second indication information to the terminal equipment, wherein the second indication information comprises information for indicating the first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel, or the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel.
The method of claim 1, wherein the method further comprises:

the network device sends third indication information to the terminal device, where the third indication information is used to indicate one or more of precoding granularity of the downlink control channel, precoding granularity of the first demodulation reference signal, precoding granularity of the downlink data channel, and precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel.
The method of claim 8, wherein the precoding granularity of the downlink control channel is related to the precoding granularity of the downlink data channel; or, the precoding granularity of the downlink control channel is related to the precoding granularity of the second demodulation reference signal; or, the precoding granularity of the first demodulation reference signal is related to the precoding granularity of the downlink data channel; alternatively, the precoding granularity of the first demodulation reference signal is correlated with the precoding granularity of the second demodulation reference signal.
A method for transmitting a downlink signal, comprising:

the method comprises the steps that a terminal device receives a downlink control channel and a first demodulation reference signal from a network device, wherein the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling a downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel;

the terminal equipment demodulates the downlink control channel according to the first demodulation reference signal;

the terminal equipment receives the downlink data channel from the network equipment and demodulates the downlink data channel according to the first demodulation reference signal.
The method of claim 10, wherein one or more of the following conditions are satisfied:

the downlink control channel and the downlink data channel adopt the same transmission mode;

the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.
The method of claim 10, wherein the method further comprises:

the terminal device receives first indication information from the network device, wherein the first indication information is used for indicating one or more of the following:

the downlink control channel and the downlink data channel adopt the same transmission mode;

the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.
The method of claim 11 or 12, wherein the same transmission mode comprises the same transmission resource, the same precoding, and the same precoding granularity.
The method of any one of claims 11-13, wherein the method further comprises:

the terminal equipment receives a second demodulation reference signal associated with the downlink data channel from the network equipment;

and the terminal equipment demodulates the downlink data channel according to the first demodulation reference signal and the second demodulation reference signal.
The method of claim 14, wherein the method further comprises:

and receiving second indication information from the network equipment, wherein the second indication information is used for indicating the time domain resource position and/or the frequency domain resource position occupied by the second demodulation reference signal.
The method of claim 14, wherein the method further comprises:

receiving second indication information from the network device, the second indication information including information indicating a first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel, or the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel.
The method of claim 10, wherein the method further comprises:

the terminal equipment receives third indication information from the network equipment, wherein the third indication information is used for indicating one or more of precoding granularity of the downlink control channel, precoding granularity of the first demodulation reference signal, precoding granularity of the downlink data channel and precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel.
The method of claim 17, wherein the precoding granularity of the downlink control channel is related to the precoding granularity of the downlink data channel; or, the precoding granularity of the downlink control channel is related to the precoding granularity of the second demodulation reference signal; or, the precoding granularity of the first demodulation reference signal is related to the precoding granularity of the downlink data channel; alternatively, the precoding granularity of the first demodulation reference signal is correlated with the precoding granularity of the second demodulation reference signal.
A transmission apparatus for a downlink signal, the apparatus being applied to a network device, the apparatus comprising:

The processing module is used for generating a downlink control channel, a first demodulation reference signal and a downlink data channel, wherein the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling the downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel;

the communication module is used for sending the downlink control channel and the first demodulation reference signal to the terminal equipment;

the communication module is further configured to send the downlink data channel to the terminal device.
The apparatus of claim 19, wherein one or more of the following conditions are satisfied:

the downlink control channel and the downlink data channel adopt the same transmission mode;

the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.
The apparatus of claim 19, wherein the communication module is further for sending first indication information to the terminal device, the first indication information being for indicating one or more of:

The downlink control channel and the downlink data channel adopt the same transmission mode;

the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.
The apparatus of claim 20 or 21, wherein the same transmission mode comprises the same transmission resource, the same precoding, and the same precoding granularity.
The apparatus according to any of claims 20-22, wherein the communication module is further configured to send the terminal device the downlink data channel associated second demodulation reference signal.
The apparatus of claim 23, wherein the communication module is further configured to send second indication information to the terminal device, the second indication information being configured to indicate a time domain resource location and/or a frequency domain resource location occupied by the second demodulation reference signal in the transmission resource.
The apparatus of claim 23, wherein the communication module is further for sending second indication information to the terminal device, the second indication information comprising information for indicating a first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel, or the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel.
The apparatus of claim 19, wherein the communication module is further configured to send third indication information to the terminal device, the third indication information being configured to indicate one or more of a precoding granularity of the downlink control channel, a precoding granularity of the first demodulation reference signal, a precoding granularity of the downlink data channel, and a precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel.
The apparatus of claim 26, wherein a precoding granularity of the downlink control channel is related to a precoding granularity of the downlink data channel; or, the precoding granularity of the downlink control channel is related to the precoding granularity of the second demodulation reference signal; or, the precoding granularity of the first demodulation reference signal is related to the precoding granularity of the downlink data channel; alternatively, the precoding granularity of the first demodulation reference signal is correlated with the precoding granularity of the second demodulation reference signal.
A downlink signal transmission apparatus, applied to a terminal device, the apparatus comprising:

the communication module is used for receiving a downlink control channel and a first demodulation reference signal from the network equipment, wherein the first demodulation reference signal is associated with the downlink control channel, the downlink control channel is used for scheduling a downlink data channel, and the first demodulation reference signal is used for demodulating the downlink control channel and the downlink data channel;

the processing module is used for demodulating the downlink control channel according to the first demodulation reference signal;

the communication module is further configured to receive the downlink data channel from the network device;

The processing module is further configured to demodulate the downlink data channel according to the first demodulation reference signal.
The apparatus of claim 28, wherein one or more of the following conditions are satisfied:

the downlink control channel and the downlink data channel adopt the same transmission mode;

the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.
The apparatus of claim 28, wherein the communication module is further for receiving first indication information from the network device, the first indication information being for indicating one or more of:

the downlink control channel and the downlink data channel adopt the same transmission mode;

the downlink control channel and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode;

the first demodulation reference signal and the downlink data channel adopt the same transmission mode;

The first demodulation reference signal and the second demodulation reference signal associated with the downlink data channel adopt the same transmission mode.
The apparatus of claim 29 or 30, wherein the same transmission mode comprises the same transmission resource, the same precoding, and the same precoding granularity.
The apparatus of any one of claim 29 to 31,

the communication module is further configured to receive a second demodulation reference signal associated with the downlink data channel from the network device;

the processing module is further configured to demodulate the downlink data channel according to the first demodulation reference signal and the second demodulation reference signal.
The apparatus of claim 32, wherein the communication module is further for receiving second indication information from the network device, the second indication information further for indicating a time domain resource location and/or a frequency domain resource location occupied by the second demodulation reference signal in the transmission resource.
The apparatus of claim 32, wherein the communication module is further for receiving second indication information from the network device, the second indication information comprising information for indicating a first time domain offset; the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the downlink control channel, or the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource position of the first demodulation reference signal, or the first time domain offset is used for representing a distance between a time domain resource position of the second demodulation reference signal and a time domain resource starting position of the downlink data channel.
The apparatus of claim 28, wherein the communication module is further for receiving third indication information from the network device, the third indication information being for indicating one or more of a precoding granularity of the downlink control channel, a precoding granularity of the first demodulation reference signal, a precoding granularity of the downlink data channel, a precoding granularity of a second demodulation reference signal; wherein the second demodulation reference signal is associated with the downlink data channel.
The apparatus of claim 35, wherein a precoding granularity of the downlink control channel is related to a precoding granularity of the downlink data channel; or, the precoding granularity of the downlink control channel is related to the precoding granularity of the second demodulation reference signal; or, the precoding granularity of the first demodulation reference signal is related to the precoding granularity of the downlink data channel; alternatively, the precoding granularity of the first demodulation reference signal is correlated with the precoding granularity of the second demodulation reference signal.
A communication device, comprising:

a processor coupled to a memory for storing a computer program or instructions for executing the computer program or instructions to implement the method of any one of claims 1-9 or the method of any one of claims 10-18.
A communication device, comprising: a processor for communicating with other devices and an interface circuit for performing the method of any of claims 1-9 or the method of any of claims 10-18.
A computer readable storage medium, having stored thereon a computer program or instructions which, when run on a computer, implement the method of any one of claims 1-9 or the method of any one of claims 10-18.