TECHNICAL FIELD

Embodiments of this application relate to the field of wireless communications, and in particular, to an antenna port determining technology.

BACKGROUND

A wireless communications system includes a terminal side device and a network side device that serves the terminal side device. The terminal side device and the network side device have protocol layers that are specified in the 3rd generation partnership project (3GPP) standard and that include a physical (PHY) layer, a media access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence (PDCP) layer, a radio resource control (RRC) layer, and the like. Protocol layers except the physical layer, including the MAC layer, the RLC layer, the PDCP layer, the RRC layer, and the like, are collectively referred to as a higher layer.

To enable the terminal side device to correctly receive downlink data (including downlink service data or downlink control signaling) transmitted in a downlink, the network side device maps, at the physical layer, a demodulation reference signal (DMRS) to at least one antenna port (DMRS antenna port for short), and sends the demodulation reference signal to the terminal side device in the downlink.

The network side device may send downlink control information (DCI) in a specific format to the terminal side device on a physical downlink control channel (PDCCH). The downlink control information includes indication information that can be used to determine antenna port numbers of DMRS antenna ports on which the downlink data is scheduled. The network side device may further indicate, to the terminal side device by using the downlink control information, at least one piece of quasi-colocation (quasi-co-located, QCL) information used when the downlink data is scheduled. Each piece of QCL information indicates that there is a QCL relationship between a DMRS antenna port and another antenna port. The terminal side device may determine the DMRS antenna ports based on the indication information and the QCL information.

In the foregoing implementation process, because there may be a relatively large quantity of candidate antenna ports, the antenna ports may not be accurately determined.

SUMMARY

In view of the foregoing technical problem, a first aspect of embodiments of this application provides an antenna port determining method, where the method is performed by a terminal side device and includes the following content:

receiving downlink control information, where the downlink control information includes quasi co-location QCL information and indication information that is used to determine an antenna port number of a first antenna port on which downlink data is scheduled, and the QCL information indicates that there is a quasi-colocation QCL relationship between the first antenna port and a second antenna port; receiving antenna port group information, where the antenna port group information is used to determine at least one antenna port group, and the at least one antenna port group includes the first antenna port; and determining the first antenna port based on the QCL information, the indication information, and the antenna port group information.

In the technical solution provided in the first aspect, the downlink control information may be carried in a physical layer message, and the antenna port group information may be carried in an RRC layer message. There is at least one piece of the downlink control information. Optionally, the QCL information and the indication information may be carried in same downlink control information. Optionally, the QCL information and the indication information may alternatively be carried in different downlink control information.

By applying the technical solution provided in the first aspect, the antenna port group information is further introduced, so that the terminal side device can search for the required first antenna port based on the antenna port group, and can accurately determine the required antenna port. Further, because the antenna port group information is introduced, a quantity of bits occupied by the indication information in the downlink control information can be correspondingly reduced, thereby reducing signaling overheads in the downlink control information.

According to the first aspect, in a first possible implementation of the first aspect, the indication information is further used to determine at least one of a quantity of code division multiplexing CDM groups corresponding to the first antenna port and a quantity of front-load symbols of the first antenna port for rate matching. In this implementation, same indication information is reused to indicate a plurality of types of information, thereby reducing signaling overheads of the indication information.

According to the first aspect or the first possible implementation of the first aspect, in a second possible implementation of the first aspect, the first antenna port is a demodulation reference signal DMRS antenna port, and the second antenna port is at least one of a channel state information-reference signal CSI-RS antenna port, a synchronization signal block SS block, a phase tracking reference signal PTRS antenna port, and a tracking reference signal TRS antenna port. In this implementation, because the first antenna port and the second antenna port have a QCL relationship, a large-scale property of a channel of the DMRS antenna port may be inferred based on a large-scale property of a channel of the CSI-RS antenna port, a channel of the SS block, a channel of the PTRS antenna port, and a channel of the TRS antenna port, thereby facilitating channel estimation during downlink data transmission on the DMRS antenna port.

According to any one of the first aspect to the second possible implementation of the first aspect, in a third possible implementation of the first aspect, the antenna port group information includes an identifier of at least one code division multiplexing CDM group or at least one DMRS antenna port number, the at least one antenna port group is the at least one DMRS group, and there is a QCL relationship between antenna ports in each of the at least one antenna port group. In this implementation, a specific implementation form that can be used to determine a DMRS antenna port group is listed, and that in this form, there is also a QCL relationship between DMRS antenna ports in the DMRS antenna port group is limited.

According to the third possible implementation of the first aspect, in a fourth possible implementation of the first aspect,

there are at least two CDM groups and two DMRS groups, a first DMRS group in the two DMRS groups includes at least one antenna port in at least one of the at least two CDM groups, and a second DMRS group in the two DMRS groups includes at least one antenna port in another CDM group in the two CDM groups. In this implementation, a manner of determining the two DMRS antenna port groups when there are at least two CDM groups is listed.

According to the fourth possible implementation of the first aspect, in a fifth possible implementation of the first aspect, in a case of transmission with one codeword,

an absolute value of a difference between a quantity of layers of the at least one antenna port included in the first DMRS group and a quantity of layers of the at least one antenna port included in the second DMRS group is allowed to be greater than 1. In this implementation, in the case of transmission with one codeword, a relationship between quantities of layers of antenna ports included in the two DMRS groups is limited. It should be noted herein that one antenna port corresponds to one layer of MIMO data. Therefore, to indicate this relationship, a person skilled in the art uses the quantity of layers of the at least one antenna port to describe a quantity of the at least one antenna port (that is, the quantity of the at least one antenna port is equal to the quantity of layers of the at least one antenna port). A maximum quantity of layers supported between the terminal side device and the network side device is a rank of a channel matrix obtained through performing channel estimation based on a reference signal.

According to the fourth possible implementation of the first aspect, in a sixth possible implementation of the first aspect, in a case of transmission with two codewords,

an absolute value of a difference between a quantity of layers of the at least one antenna port included in the first DMRS group and a quantity of layers of the at least one antenna port included in the second DMRS group is not greater than 1, a first codeword in the two codewords corresponds to the first DMRS group, and a second codeword corresponds to the second DMRS group. In this implementation, in the case of transmission with two codewords, a relationship between quantities of layers of antenna ports included in the two DMRS groups is limited.

A second aspect of the embodiments of this application provides a terminal side device, and the terminal side device includes a receiving unit and a processing unit. The receiving unit is configured to perform a receiving action according to any one of the first aspect to the possible implementations of the first aspect, and the processing unit is configured to perform processing actions such as determining according to any one of the first aspect to the possible implementations of the first aspect. In specific physical implementation, the receiving unit may be a receiving circuit or a receiver, the processing unit may be a processing circuit or a processor, and the sending unit may be a sending circuit or a transmitter. Optionally, the terminal side device may be an independent terminal device, or may be a chip or a circuit system in the terminal device. The chip or the circuit system includes a plurality of gate circuits to implement functions of the foregoing functional units. The terminal side device provided in the second aspect can be used to implement beneficial effects achieved in any one of the first aspect to the possible implementations of the first aspect. Details are not described again.

A third aspect of the embodiments of this application provides a terminal side device, including a processor and a memory, where the memory stores instruction code, and when the code is invoked by the processor, the method according to any one of the first aspect to the possible implementations of the first aspect is implemented. Optionally, the terminal side device provided in the third aspect may be a chip system, or an independent terminal device including the chip system. The terminal side device provided in the third aspect can be used to implement beneficial effects achieved in any one of the first aspect to the possible implementations of the first aspect. Details are not described again.

A fourth aspect of the embodiments of this application provides an antenna port determining method, applied to a network side device, and including the following content:

sending downlink control information, where the downlink control information includes quasi-colocation QCL information and indication information that is used to determine an antenna port number of a first antenna port on which downlink data is scheduled, and the QCL information indicates that there is a QCL relationship between the first antenna port and a second antenna port; and

sending antenna port group information, where the antenna port group information is used to determine at least one antenna port group, the at least one antenna port group includes the first antenna port, and

the QCL information, the indication information, and the antenna port group information are used by a terminal side device to determine the first antenna port.

In the technical solution provided in the fourth aspect, the downlink control information may be carried in a physical layer message, and the antenna port group information may be carried in an RRC layer message. There is at least one piece of the downlink control information. Optionally, the QCL information and the indication information may be carried in same downlink control information. Optionally, the QCL information and the indication information may alternatively be carried in different downlink control information.

The technical solution provided in the fourth aspect is applied to correspond to the technical solution provided in the first aspect, and has technical effects of the technical solution provided in the first aspect.

According to the fourth aspect, in a first possible implementation of the fourth aspect, before the sending the downlink control information and the antenna port group, the method further includes:

determining the first antenna port, and determining the indication information and the antenna port group information based on the first antenna port.

In the first possible implementation of the fourth aspect, the network side device may determine the indication information and the antenna port group information based on the first antenna port on which the downlink data is scheduled, so that the terminal side device can determine the first antenna port based on the received indication information and the antenna port group information. This ensures consistent understanding of the first antenna port by the network side device and the terminal side device.

According to the fourth aspect or the first possible implementation of the fourth aspect, in a second possible implementation of the fourth aspect, the indication information is further used to determine at least one of a quantity of code division multiplexing CDM groups corresponding to the first antenna port and a quantity of front-load symbols of the first antenna port for rate matching.

According to the technical solution provided in the second possible implementation of the fourth aspect, same indication information is reused to indicate a plurality of types of information, thereby reducing signaling overheads of the indication information.

Optionally, the first antenna port is a demodulation reference signal DMRS antenna port, and the second antenna port is at least one of a channel state information-reference signal CSI-RS antenna port, a synchronization signal block SS block, a phase tracking reference signal PTRS antenna port, and a tracking reference signal TRS antenna port. In this implementation, because the first antenna port and the second antenna port have a QCL relationship, a large-scale property of a channel of the DMRS antenna port may be inferred based on a large-scale property of a channel of the CSI-RS antenna port, a channel of the SS block, a channel of the PTRS antenna port, and a channel of the TRS antenna port, thereby facilitating channel estimation during downlink data transmission on the DMRS antenna port.

Optionally, the antenna port group information includes an identifier of at least one code division multiplexing CDM group or at least one DMRS antenna port number, the at least one antenna port group is the at least one DMRS group, and there is a QCL relationship between antenna ports in each of the at least one antenna port group. In this implementation, a specific implementation form that can be used to determine a DMRS antenna port group is listed, and that in this form, there is also a QCL relationship between DMRS antenna ports in the DMRS antenna port group is limited.

Optionally, there are at least two CDM groups and two DMRS groups, a first DMRS group in the two DMRS groups includes at least one antenna port in at least one of the at least two CDM groups, and a second DMRS group in the two DMRS groups includes at least one antenna port in another CDM group in the two CDM groups. In this implementation, a manner of determining the two DMRS antenna port groups when there are at least two CDM groups is listed.

Optionally, in a case of transmission with one codeword, an absolute value of a difference between a quantity of layers of the at least one antenna port included in the first DMRS group and a quantity of layers of the at least one antenna port included in the second DMRS group is allowed to be greater than 1. In this implementation, in the case of transmission with one codeword, a relationship between quantities of layers of antenna ports included in the two DMRS groups is limited.

Optionally, in a case of transmission with two codewords, an absolute value of a difference between a quantity of layers of the at least one antenna port included in the first DMRS group and a quantity of layers of the at least one antenna port included in the second DMRS group is not greater than 1, a first codeword in the two codewords corresponds to the first DMRS group, and a second codeword corresponds to the second DMRS group. In this implementation, in the case of transmission with one codeword, a relationship between quantities of layers of antenna ports included in the two DMRS groups is limited.

A fifth aspect of the embodiments of this application provides a network side device, and the network side device includes a sending unit and a processing unit. The sending unit is configured to perform a sending action according to any one of the fourth aspect to the possible implementations, and the processing unit is configured to perform processing actions such as determining according to any one of the first aspect to the possible implementations of the first aspect. In specific physical implementation, the processing unit may be a processing circuit or a processor, and the sending unit may be a sending circuit or a transmitter. Optionally, the network side device may be an independent network device (for example, a base station), or may be a chip or a circuit system in the network device. The chip or the circuit system includes a plurality of gate circuits to implement functions of the foregoing functional units. The terminal side device provided in the fifth aspect can be used to implement beneficial effects achieved in any one of the fourth aspect to the possible implementations of the fourth aspect. Details are not described again.

A sixth aspect of the embodiments of this application provides a network side device, including a processor and a memory, where the memory stores instruction code, and when the code is invoked by the processor, the method according to any one of the fourth aspect to the possible implementations is implemented. Optionally, the network side device provided in the sixth aspect may be a chip system, or a network device (such as a base station) including the chip system. The network side device provided in the sixth aspect can be used to implement beneficial effects achieved in any one of the fourth aspect to the possible implementations of the fourth aspect. Details are not described again.

A seventh aspect of this application provides a computer storage medium, where the computer storage medium stores code, and the code is used to implement the method according to any one of the first aspect to the possible implementations of the first aspect, and the fourth aspect to the possible implementations of the fourth aspect. The computer storage medium provided in the seventh aspect may be included in a chip system, or an independent terminal device or network device including the chip system. The computer storage medium provided in the seventh aspect can be used to implement beneficial effects achieved in any one of the first aspect to the possible implementations of the first aspect, and the fourth aspect to the possible implementations of the fourth aspect. Details are not described again.

