Abstract: This application relates to a downlink control information indication method during coordinated multipoint transmission/reception in a wireless communications system. For a plurality of network side devices that send downlink data to user equipment on a same carrier and in a same subframe, downlink data transmission information used when the network side devices separately send the downlink data is indicated by using a plurality of pieces of downlink control information. Therefore, diversity transmission and/or multi-stream transmission in a multipoint coordination scenario are/is supported, and when the user equipment cannot normally receive downlink data sent by some network side devices because some downlink control information encounters an error, the user equipment may still receive, based on an indication of remaining downlink control information that encounters no error, downlink data sent by a network side device corresponding to the remaining downlink control information that encounters no error.

Abstract: The present disclosure relates to the field of mobile communications technologies, and in particular, to a signal transmission method and an apparatus. In the signal transmission method, user equipment receives, from a base station, first information in a physical downlink control channel, where the first information is used for determining precoding information of a sounding reference signal (SRS). The user equipment determines precoding information of the SRS based on the first information. The user equipment performs, based on the precoding information, precoding on the SRS to generate a precoded signal, and sends the precoded signal to the base station.

Abstract: Embodiments of this application provide a power headroom reporting method and apparatus. Impact of introduction of multi-beam transmission, a plurality of time-frequency resource configurations, or an uplink multi-waveform technology on a power headroom is considered, so that the power headroom is calculated and reported more accurately, to help a network side make a scheduling decision, thereby improving communication performance.

Abstract: Example quasi co-location information determining methods and apparatus are described. One example method includes determining a quantity X of pieces of quasi co-location QCL information, where X is a positive integer. When it is determined that the quantity X of pieces of QCL information is two, and that DCI corresponding to a current data channel does not indicate QCL information of an antenna port of the data channel, or that an interval between the current data channel and the DCI corresponding to the data channel is less than a threshold, two pieces of default QCL information of the antenna port of the data channel are determined.

Abstract: A communication method, including: receiving a reference signal, where the reference signal is used for channel measurement; sending CSI, where the CSI is used to indicate one or more measured values, and the measured values are used to determine a precoding matrix, or the measured values are a precoding matrix. The measured value is related to a first group of base vectors and a second group of base vectors, or the measured value is related to a Kronecker product of the first group of base vectors and the second group of base vectors; the first group of base vectors includes an inverse discrete Fourier transform OFT vector or a Kronecker product of two IDFT vectors, and the second group of base vectors include a discrete Fourier transform DFT vector.

Abstract: Embodiments of the present invention provide a method which includes: a terminal device is configured to send precoding matrix indicator information to a radio access network device, wherein the precoding matrix indicator information is used to indicate a precoding matrix in a codebook, and the codebook comprises information about a quantity of corresponding antenna panels and information about a phase difference between different corresponding antenna panels; and the terminal device receives downlink data from the radio access network device.

Abstract: A data transmission method and apparatus are provided. The method includes: receiving control information from a network side device, wherein the control information comprises transmission parameter indication information, wherein the transmission parameter indication information is used to indicate a quantity of transport layers for at least two codewords and port numbers of ports for the at least two codewords; and determining, based on the transmission parameter indication information, a quantity of transport layers for at least two codewords and port numbers of ports for the at least two codewords, wherein ports used by different codewords of the at least two codewords are non-quasi-co-location, and ports used by one codeword of the at least two codewords are quasi-co-location when the codeword has more than one port.

Abstract: One example method includes receiving first indication information through a higher layer signaling, the first indication information indicating an available codebook subset, receiving downlink control information, determining a precoding matrix corresponding to a transmission precoding matrix indicator (TPMI) and a transmission rank obtained from the downlink control information, where the precoding matrix belongs to the available codebook subset indicated by the first indication information, precoding a signal based on the determined precoding matrix, and sending the precoded signal to a network device.

Abstract: A power configuration method and a device, the power configuration method including sending, by a first network device, M power configuration parameters to a second network device, where the M power configuration parameters are corresponding to M antenna port sets, wherein at least one of the M antenna port sets belongs to the first network device, where each power configuration parameter is used to calculate power of a downlink data channel between a corresponding antenna port set and the second network device, and where M is an integer greater than or equal to 2.

Abstract: Embodiments of the present disclosure provide a downlink synchronization method, an apparatus, and a system, and relate to the communications field, so as to reduce downlink synchronization complexity and improve downlink synchronization efficiency. According to the downlink synchronization method, abase station sends downlink synchronization reference information to UE by using dedicated signaling or a system message, where the downlink synchronization reference information is used to instruct the UE to perform downlink synchronization in a second cell by referring to a downlink synchronization channel of a first cell; and the base station sends, in the second cell according to location information of the UE, a beam including a downlink synchronization channel to the UE, where the first cell and the second cell include an overlapped coverage area. The embodiments of the present disclosure are applied to synchronization channel sending.

Abstract: A data symbol transmission method and a wireless network device are provided. The device includes: an information determining unit, configured to determine a location at which hardware switching needs to be performed in a current subframe and switching time of the hardware switching; a configuration unit, configured to configure, according to the switching time, a first guard period for a first data symbol corresponding to the location, where a length of the first guard period is greater than or equal to that of the switching time; where the configuration unit is further configured to: use, as a second data symbol, a data symbol in the subframe other than the first data symbol, and configure a second guard period for the second data symbol; and a sending unit, configured to send the subframe to another wireless network device. Resource utilization can be improved, and a system capacity can be increased.

Abstract: A CSI-RS measurement feedback method and device are provided to optimize analog and digital precoding. A network device sends S CSI-RSs to a terminal device. Each CSI-RS corresponds to one antenna port number. The terminal device sends M antenna port numbers that correspond to M CSI-RSs and sends a PMI that corresponds to a channel matrix H or the quantization result of a channel matrix H to the network device. The terminal device selects the M antenna port numbers that correspond to the M CSI-RSs from the S antenna port numbers that correspond to the S CSI-RSs, and feeds back the M antenna port numbers to the network device.

Abstract: In accordance with an embodiment, the application discloses a communication method that includes the operations: generating downlink control information DCI; and sending the DCI to a terminal device. The DCI includes indication information used to indicate a single codeword scheduled by using the DCI, or a correspondence between a single codeword scheduled by using the DCI and a first resource. Alternatively, the DCI includes a first number of a hybrid automatic repeat request HARQ process corresponding to a single codeword scheduled by using the DCI, where a quantity of values of the first number is greater than a quantity of values of a second number of an HARQ process used by either one codeword of DCI used to schedule two codewords. In embodiments of the application, a utilization rate of an HARQ buffer can be improved.

Abstract: Embodiments of this application provide a power headroom reporting method and apparatus. Impact of introduction of multi-beam transmission, a plurality of time-frequency resource configurations, or an uplink multi-waveform technology on a power headroom is considered, so that the power headroom is calculated and reported more accurately, to help a network side make a scheduling decision, thereby improving communication performance.

Abstract: Embodiments of the present disclosure provide a downlink synchronization method, an apparatus, and a system, and relate to the communications field, so as to reduce downlink synchronization complexity and improve downlink synchronization efficiency. According to the downlink synchronization method, a base station sends downlink synchronization reference information to UE by using dedicated signaling or a system message, where the downlink synchronization reference information is used to instruct the UE to perform downlink synchronization in a second cell by referring to a downlink synchronization channel of a first cell; and the base station sends, in the second cell according to location information of the UE, a beam including a downlink synchronization channel to the UE, where the first cell and the second cell include an overlapped coverage area. The embodiments of the present disclosure are applied to synchronization channel sending.

Abstract: This application provides a communication method, to provide a codebook of a higher-order precoding matrix, and help increase a quantity of layers of data, thereby helping improve a data transmission capability and improving a throughput. The method includes: receiving, by a first device, a reference signal used for channel measurement; and sending, by the first device, at least one precoding matrix indicator PMI and a rank indication RI based on the reference signal, where the PMI is used to indicate a precoding matrix in a codebook corresponding to the RI, the precoding matrix in the codebook includes a plurality of matrices in a one-to-one correspondence with a plurality of antenna port groups, a matrix corresponding to one antenna port group or each of at least two antenna port groups has two different inter-antenna-port-group phase factors, and any two column vectors in the precoding matrix are orthogonal to each other.

Abstract: A communication method and an apparatus is provided. The method includes: determining, by a first network device for a first carrier, association information between a first resource and at least one of a first HARQ entity, a first MAC entity, or a first RLC entity, and sending configuration information to a terminal device, where the configuration information includes the association information between the first resource and the at least one of the first HARQ entity, the first MAC entity, or the first RLC entity; and receiving, by the terminal device, the configuration information, receiving first data, determining that the first data corresponds to the first resource, and determining, based on the configuration information and the first data that corresponds to the first resource, at least one of the first HARQ entity, the first MAC entity, or the first RLC entity corresponding to the first data, HARQ performance is ensured.

Abstract: This application provides a communication method, a network device, a terminal device, and a system. The communication method includes: determining, by a network device, a plurality of pieces of quasi co-location information, where the plurality of pieces of quasi co-location information correspond to a plurality of antenna port sets of a first control resource set, and each piece of quasi co-location information in the plurality of pieces of quasi co-location information is used to indicate a quasi co-location characteristic of an antenna port set corresponding to each piece of quasi co-location information; and sending, by the network device, the plurality of pieces of quasi co-location information to a terminal device. In embodiments of this application, the plurality of pieces of quasi co-location information are used to indicate the quasi co-location characteristics of the antenna ports to the terminal device, to improve communication efficiency.

Abstract: Embodiments of the present invention relate to the communications field, and disclose an information transmission method and device to implement beamforming on an SRS. A specific solution is as follows: A base station configures at least one first resource for a UE, where the first resource is used by the UE to transmit a target channel and/or signal; and the base station transmits first indication information to the UE, where the first indication information is used to indicate a correspondence between the first resource and a beam, or the first indication information is used to indicate a correspondence between the first resource and a second resource. The embodiments of the present invention are used in a beamforming process.

Abstract: This application provides a transmission precoding matrix indication method and a device. The method includes: determining a bit quantity of a transmission precoding matrix indicator field corresponding to a subband scheduled for uplink based on downlink control information received from a network device, where the bit quantity of the transmission precoding matrix indicator field corresponding to the subband is related to a quantity of subbands corresponding to the resource scheduled for uplink; and further, determining an uplink transmission precoding matrix corresponding to the subband based on the bit quantity of the transmission precoding matrix indicator field corresponding to the subband and the uplink transmission layer quantity. A transmission precoding matrix indicator field can be effectively used, and control channel resource utilization is improved.