Abstract: This application provides an information transmission method and apparatus. The method includes: receiving, by a terminal device, a plurality of pieces of downlink control information DCI, where each of the plurality of pieces of DCI is used to trigger reporting of one piece of UCI and indicate a physical uplink control channel PUCCH resource carrying the UCI, the UCI includes at least one piece of channel state information CSI and response information, and PUCCH resources indicated by the plurality of pieces of downlink DCI occupy at least one same orthogonal frequency division multiplexing OFDM symbol; and sending, by the terminal device, target UCI on a target PUCCH resource, where the target UCI includes UCI triggered by the plurality of pieces of DCI, and the target PUCCH resource is one of the PUCCH resources indicated by the plurality of pieces of DCI. In this way, aperiodic CSI triggered by DCI can be transmitted on a PUCCH resource.

Abstract: Embodiments of a channel state information (CSI) reporting method and apparatus are disclosed. A method includes: receiving, by a first communications apparatus, reference signals from a second communications apparatus; and performing, by the first communications apparatus, channel measurement based on the reference signals, and sending first CSI to the second communications apparatus in a time unit whose identifier is m, where the first CSI is used to indicate a channel state in a first reference time unit and a channel state in a second reference time unit, where an identifier of the first reference time unit is m?n1, an identifier of the second reference time unit is m?n1?n2, where m, n1, and n2 are integers, and n2 is not equal to 0. This way, matching is improved between CSI applied by a network device and a channel that is at a current moment.

Abstract: This application provides a data transmission method, a network device, and a terminal device. The method includes: generating, by the network device, first information, where a value of a bit included in the first information is used to indicate a demodulation reference symbol (DMRS) port combination in a second set, each DMRS port combination in the second set belongs to a first set, the first set includes a plurality of DMRS port combinations, the DMRS port combination includes at least one DMRS port, and a quantity of DMRS port combinations included in the second set is less than a quantity of DMRS port combinations included in the first set; and sending, by the network device, the first information to the terminal device. According to embodiments of this application, signaling overheads can be reduced.

Abstract: Channel state information (CSI) sending methods, apparatuses, and systems are disclosed. In an implementation, a method comprises: receiving, by a network device from a terminal device, channel state information (CSI) comprising a rank indicator (RI), indication information, and a second precoding matrix indicator (PMI2); determining, by the network device, the RI and the indication information from the CSI; determining, by the network device, the PMI2 based on the RI and the indication information; and determining, by the network device, a precoding matrix W based on the RI and the PMI2, wherein W satisfies W=W1×W2, W is an Nt by L matrix, W1 is an Nt by 2I matrix, W2 is a 2I by L matrix, L is a rank indicated by the RI, Nt is greater than or equal to L, and I is an integer greater than or equal to 1.

Abstract: This application provides an example communication method and apparatus. The communication method is performed in a communications system, where N antenna ports are configured for the terminal device, N is an integer greater than or equal to 2, the N antenna ports correspond to T antenna port combination modes, each antenna port combination mode corresponds to M antenna ports in the N antenna ports, and each antenna port combination mode set includes at least one antenna port combination mode. The communication method includes receiving, by the network device, first indication information from the terminal device, where the first indication information is used to indicate a first antenna port combination mode set. The method also includes determining, by the network device, K antenna ports in the N antenna ports based on the first antenna port combination mode set and sending, by the network device, second indication information to the terminal device.

Abstract: This application provides sounding reference signal transmission methods and apparatuses. One method comprises: determining, by a terminal device, that a sounding reference signal (SRS) to be transmitted is an nSRSth transmission of a plurality of SRS transmissions, wherein nSRS is a non-negative integer; selecting, by a terminal device, an antenna group of ? antenna groups to transmit the sounding reference signal (SRS) based on ? and nSRS, such that when sending the SRS for 2? times, the SRS is sent through each of the ? antenna groups at least once, wherein ? is a positive integer greater than or equal to 3; and sending, by the terminal device during the nSRSth transmission, the SRS through antenna ports comprised in the selected antenna group.

Abstract: A method in the embodiments of this application includes: generating, by a terminal device, first information, where the first information includes parameters q, m1, m2, . . . , mL, and indication information of a vector V; q is an integer, and q<Q; Q is an integer, and Q>1; 0?ml?N?1, and 1?l?L; L>1, N, L, and l are integers, and N is a quantity of subbands in a frequency domain bandwidth; and the vector V includes L elements and satisfies V=Fq×C, where C is a vector formed by N elements c1, . . . , cN, C=[c1 c2 . . . cN]T, ck is used to indicate channel state information on a kth frequency domain subband, ck is a complex number, a modulus of ck is |ck|?1, and 1?k?N; and sending, by the terminal device, the first information to a network device.

Abstract: Embodiments of this application provide a precoding matrix indication method, a communications apparatus, and a storage medium. A precoding matrix of each of K frequency-domain units satisfies W=W1×W2, and elements in W2 in the K frequency-domain units are represented by P elements that are relatively few. A terminal device reports third indication information, where the third indication information includes first indication information and the second indication information, and the first indication information and the second indication information are independently encoded. The first indication information is used to indicate the P elements, and the second indication information is used to indicate P. Therefore, the terminal device can adjust a quantity of information bits of the second indication information based on a channel condition change, thereby improving precoding matrix reporting efficiency.

Abstract: This application discloses a data transmission solution. A terminal device generates channel state information and data for transmission in a data channel. The transmit power of the data channel is determined based on the number of bits used to transmit the data and the number of bits used to transmit the channel state information. The solution of this application reduces bit error probability and improves data decoding accuracy.

Abstract: An interference power measurement method and a device are provided. The method includes: receiving, by a terminal, first signaling that carries first indication information, where the first indication information is used to indicate n first channel state information-reference signal CSI RS resources, and a jth first CSI RS resource is associated with a power parameter Pc,j; and sending, by the terminal, a channel quality indicator CQI, where the CQI is determined based on a total interference power. The total interference power is a linear weighting result of an interference power measured on each of the n first CSI RS resources and an interference power I0 measured on a zero power CSI RS resource. A weighting coefficient of an interference power Ij measured on the jth first CSI RS resource is a function of the power parameter Pc,j, and a weighting coefficient of I0 is a function of 1 - ? j = 1 n ? P c , j .

Abstract: Embodiments of this application provide a precoding matrix indication method, a communications apparatus, and a storage medium. A precoding matrix of each of K frequency-domain units satisfies W=W1×W2, and elements in W2 in the K frequency-domain units are represented by P elements that are relatively few. A terminal device reports third indication information, where the third indication information includes first indication information and the second indication information, and the first indication information and the second indication information are independently encoded. The first indication information is used to indicate the P elements, and the second indication information is used to indicate P. Therefore, the terminal device can adjust a quantity of information bits of the second indication information based on a channel condition change, thereby improving precoding matrix reporting efficiency.

Abstract: Embodiments of the present invention disclose a communication method and a device. Configuration information indicating one or more spatial domain beam basis vector groups and Q thresholds is received from a network device, where the Q thresholds correspond one-to-one to spatial domain beam basis vectors in the one or more spatial domain beam basis vector groups. L spatial domain beam basis vectors are selected from a spatial domain beam basis vector group set. K frequency domain basis vectors are selected from a frequency domain basis vector set for each of the L spatial domain beam basis vectors.

Abstract: One example method for measuring a channel state information reference signal includes receiving, from a network device, a partial channel state information reference signal resource sets selected from a plurality of channel state information reference signal resource sets and indication information indicating one or more resource sets for channel measurement, which are from the partial channel state information reference signal resource sets, and performing channel measurement by using the one of the one or more resource sets for channel measurement indicated by the indication information.

Abstract: This application provides a data transmission method, terminal device, and network device. The method includes: sending, by a terminal device, at least one precoded reference signal on at least one reference signal resource corresponding to a first PRG, where different precoding matrixes are used for different reference signals, and the first PRG is a PRG used to transmit a reference signal; receiving, by the terminal device, resource indication information, where the resource indication information indicates a reference signal resource that is corresponding to a second PRG and that is in the at least one reference signal resource, and the second PRG is a PRG used to transmit a physical uplink shared channel (PUSCH); and sending, by the terminal device, a precoded PUSCH on the second PRG based on the resource indication information, where a precoding matrix used for the PUSCH is a precoding matrix used for a reference signal sent on the reference signal resource corresponding to the second PRG.

Abstract: Embodiments of this application provide an SRS sending method, an SRS receiving method, and a device. A manner of determining an antenna used to send an SRS is provided. In addition, a case in which one subframe includes a plurality of symbols is considered by using a quantity of first time units that are used by a terminal device to send an SRS in one uplink subframe and a case in which one antenna is enabled to implement continuous sending as much as possible is also considered by using a quantity of first time units that are consecutively used to send the SRS in one subframe by using a same antenna.

Abstract: The present disclosure relates to reference symbol indication methods, devices, and systems. One example method includes receiving, by a user equipment, a target parameter including a target reference symbol indication sent by a base station, determining a target transmission mode and target reference symbol information based on the target parameter and a preset reference symbol mapping relationship, generating a target reference symbol based on the target reference symbol information, and demodulating data based on the target reference symbol and the target transmission mode, where the preset reference symbol mapping relationship includes a mapping relationship among a reference symbol indication, reference symbol information, and a transmission mode.

Abstract: This application provides a channel state information transmission method, an access network device, and a terminal device. The method includes: receiving, by an access network device, CSI reported by a terminal device, where the CSI includes a first PMI and a second PMI; and determining, by the access network device based on the first PMI and the second PMI, a precoding matrix W whose rank is greater than or equal to 2, where W meets W=W1×W2, and the second PMI is used to indicate some column vectors in W2. According to the method in the embodiment, overheads of feeding back the CSI by the terminal device are effectively reduced.

Abstract: This application discloses a precoding matrix index (PMI) reporting method, and related communications apparatus and medium. The method includes: determining an rank indicator (RI) and a PMI, where the PMI is used to determine R precoding matrices W1, . . . , WR. An rth precoding matrix Wr in the R precoding matrices satisfies Wr=W1×W2,r, where an lth row of W2,r is obtained by performing DFT transform on an lth row of a matrix V2,r, and R is indicated by the RI. The PMI includes first indication information and second indication information. The first indication information includes location index information. The location index information is used to indicate Km,r element locations tr,m,1, . . . , ?{1, . . . , T} on an mth row of V2,r. The second indication information is used to indicate Km,r complex coefficients at the element locations tr,m,1, . . . , on the mth row of V2,r. V2,r is determined based on the Km,r element locations and the Km,r complex coefficients.

Abstract: Embodiments of this application provide a precoding matrix indication method, a communications apparatus, and a storage medium. A precoding matrix of each of K frequency-domain units satisfies W=W1×W2, and elements in W2 in the K frequency-domain units are represented by P elements that are relatively few. A terminal device reports third indication information, where the third indication information includes first indication information and the second indication information, and the first indication information and the second indication information are independently encoded. The first indication information is used to indicate the P elements, and the second indication information is used to indicate P. Therefore, the terminal device can adjust a quantity of information bits of the second indication information based on a channel condition change, thereby improving precoding matrix reporting efficiency.

Abstract: A bit field indication manner is provided. A first field is determined, where the first field includes T1 bits, at least one of the T1 bits indicates at least two elements {bi0, bi1, . . . , bik} in a set B, the at least one bit further indicates at least one element {?j0, ?j1, . . . , ?jh} in a set ?, and at least one element in {bi0, bi1, . . . , bik} and at least one element in {?j0, ?j1, . . . , ?jh} are used to form a preceding matrix, where the set B={b0, b1, L, bT2?1}, an element in the set B is a vector with a length of N/4, the set ?={?0, ?1, . . . , ?S?1}, an element in ? is a complex number of a unit amplitude.