Abstract: Embodiments of the present invention provide a data transmission method, including: allocating, based on a power ratio value of near user equipment to far user equipment in two paired user equipments, a transmit power to each of the near user equipment and the far user equipment, where the power ratio value is a ratio in a first ratio set, at least one ratio in the first ratio set can be selected from a second ratio set. Therefore, according to the embodiments of the present invention, a plurality of power ratio values of near user equipment to far user equipment in two paired user equipments can be provided, thereby increasing flexibility of a base station for the near user equipment and the far user equipment, and helping increase a performance gain that can be obtained by MUST transmission.

Abstract: This application relates to the field of mobile communications, and in particular, to technologies of obtaining channel state information in a wireless communications system. In a channel information obtaining method, a base station obtains channel state matrix information of some channels based on uplink reference information sent by a terminal and partial channel state information of channels between the base station and the terminal, to obtain channel state matrix information of the channels between the base station and the terminal. Base on this method, relatively complete channel state matrix information of the channels between the base station and the terminal can be obtained. This helps the base station select an appropriate parameter to transmit data to the terminal without causing an additional delay, performance loss, or cost increase, or consuming more time-frequency resources used for the uplink reference signal.

Abstract: Embodiments of the present invention provide a method for feeding back channel state information, a user equipment, and a base station, to improve feedback precision of channel state information. The method includes: receiving a reference signal sent by a base station; selecting a precoding matrix W from a codebook according to the reference signal, where a column vector of the precoding matrix W may be expressed as ?[v ej?v]T, v=[1 ej?]; and sending a precoding matrix indicator PMI to the base station, where the PMI is corresponding to the selected precoding matrix W. The present invention may further improve quantization precision and achieve balance between overheads and the quantization precision. The base station performs precoding on a sent signal according to a fed back precoding matrix indicator, which can improve precoding precision, thereby improving a data transmission rate and system throughput.

Abstract: Embodiments of the present invention disclose a signal transmission method, a system, and a device. When measuring a reference signal and determining channel quality, UE obtains a difference between codeword to CSI-RS mapping relationships by using a channel quality measurement model, may calculate an optimized mapping relationship by means of measurement, and determines at least one mapping relationship from these mapping relationships, to adjust a codeword to CSI-RS mapping relationship of a channel, thereby improving system flexibility and increasing channel resource utilization.

Abstract: Embodiments of the present invention disclose a precoding matrix indicator feedback method, receiving method, and apparatus. User equipment UE receives a reference signal sent by a base station; the UE selects, based on the reference signal, a precoding matrix for each first subband of N first subbands in a system transmission bandwidth from a codebook, where the codebook includes at least two precoding matrixes, and each precoding matrix is denoted by at least a first precoding matrix indicator PMI and a second PMI, where each first subband of the N first subbands corresponds to a second PMI, and each second subband of M second subbands corresponds to a first PMI; and the UE feeds back the first PMI corresponding to each second subband to the base station, and feeds back the second PMI corresponding to each first subband to the base station.

Abstract: The present invention provides a data transmission method and device. The method includes: performing, by the first communications equipment, multi-stream data transmission with the second communications equipment according to a first antenna port, where the first antenna port is an antenna port, of the first communications equipment, satisfying a condition for multi-stream data transmission between the first communications equipment and the second communications equipment. The method provided in embodiments of the present invention improves applicability of a multi-stream data transmission system for line of sight propagation.

Abstract: Embodiments of the present invention provide a signal transmission method and device. The method includes: determining, by a sending device, a target precoding matrix V, where V=(H)?1·{tilde over (H)}, H indicates a channel matrix between the sending device and a receiving device, {tilde over (H)} indicates an equivalent channel matrix between the sending device and the receiving device, ({tilde over (H)}H·{tilde over (H)}) or ({tilde over (H)}·{tilde over (H)}H) is a diagonal matrix, and {tilde over (H)} is related to a transmission distance D between the sending device and the receiving device and an element spacing of an antenna of the receiving device; and sending, by the sending device, a signal to the receiving device according to the target precoding matrix V. Because {tilde over (H)} meets a characteristic that ({tilde over (H)}H·{tilde over (H)}) or ({tilde over (H)}·{tilde over (H)}H) is a diagonal matrix, a channel corresponding to {tilde over (H)} can support multiple data stream transmission.

Abstract: Embodiments of the present invention provide a method for feeding back channel state information, a user equipment, and abase station, to improve feedback precision of channel state information. The method includes: receiving a reference signal sent by a base station; selecting a precoding matrix W from a codebook according to the reference signal, where a column vector of the precoding matrix W may be expressed as ?[V ej?v]T, v=[1 ej?]; and sending a precoding matrix indicator PMI to the base station, where the PMI is corresponding to the selected precoding matrix W. The present invention may further improve quantization precision and achieve balance between overheads and the quantization precision. The base station performs precoding on a sent signal according to a fed back precoding matrix indicator, which can improve precoding precision, thereby improving a data transmission rate and system throughput.

Abstract: Embodiments of the present invention disclose a signal transmission method, a system, and a device. When measuring a reference signal and determining channel quality, UE obtains a difference between codeword to CSI-RS mapping relationships by using a channel quality measurement model, may calculate an optimized mapping relationship by means of measurement, and determines at least one mapping relationship from these mapping relationships, to adjust a codeword to CSI-RS mapping relationship of a channel, thereby improving system flexibility and increasing channel resource utilization.

Abstract: Embodiments of the present invention provide a method for feeding back a channel quality indicator, and a method and an apparatus for sending resource scheduling information. An apparatus for feeding back a channel quality indicator includes: a determining module, configured to determine a feedback granularity of a CQI according to a system bandwidth, a CQI feedback mode, and antenna port quantity information specified by a network device; and a feedback module, configured to feed back the CQI to the network device according to the feedback granularity of the CQI. The method for feeding back a channel quality indicator, and the method and the apparatus for sending resource scheduling information provided in the embodiments of the present invention are used to reduce system overheads.

Abstract: A transmit diversity method, a device, and a system are described herein. The method includes: measuring, by a second network device, channel state information based on a pilot signal, and sending rank index information and precoding matrix index information to a first network device based on the channel state information; receiving, by the first network device, the rank index information and the precoding matrix index information that are sent by the second network device; determining a diversity coding scheme based on the rank index information; determining a precoding matrix based on the precoding matrix index information; and performing transmission processing on to-be-transmitted data based on the diversity coding scheme and the precoding matrix.

Abstract: The present invention provides a codebook configuration method and user equipment. The UE receives a reference signal that is of an antenna whose quantity of antenna ports is X and that is sent by a base station and configuration information of a codebook subset restriction for the quantity X of antenna ports, where the configuration information of the codebook subset restriction for the quantity X of antenna ports includes first configuration information and second configuration information; determines, according to the configuration information of the codebook subset restriction for the quantity X of antenna ports, a precoding matrix on which channel measurement and feedback need to be performed; and obtains, by means of measurement according to the reference signal, the precoding matrix on which channel measurement and feedback need to be performed and that is of antenna ports.

Abstract: A precoding matrix set determining method and apparatus, and a parameter indication information sending method and apparatus are provided. The precoding matrix set determining method include: determining, by a first network device, a parameter used for determining a precoding matrix set, where the parameter includes at least one of a phase parameter, an amplitude parameter, a quantity of vectors in the precoding matrix set, a quantity of vectors in a first codebook set in dual-codebook feedback, and a quantity of vectors in a second codebook set in the dual-codebook feedback, and the parameter is not fixed; and using the parameter to determine the precoding matrix set, where the precoding matrix set includes at least one precoding matrix. By using this solution, flexibility of feeding back a precoding matrix indicator is improved.

Abstract: The present invention discloses a channel state information CSI reporting method and apparatus, and a base station antenna. In the method, at least one precoding matrix is selected from a codebook based on a reference signal sent by a base station, and CSI is sent to the base station. The CSI includes at least one selected precoding matrix indicator PMI, and the PMI is corresponding to the selected at least one precoding matrix. At least one precoding matrix W included in the codebook may be expressed as W=W1W2, where is a Kronecker product, and at least one of W1 or W2 is an antenna selection matrix. Therefore, in embodiments of the present invention, the base station can select, according to the at least one precoding matrix that is fed back, one or more antenna ports to send a signal.

Abstract: A method for measuring and feeding back channel information and a corresponding apparatus are provided. In an embodiment the method includes determining, by a first network device, a first codebook from a first codebook set, wherein the first codebook set comprises at least two first codebooks, wherein a sub-vector Wx of each first codebook is formed by a zero vector and a non-zero vector, wherein vectors forming the Wx are associated with different groups of antenna ports, wherein each first codebook comprises at least one first sub-vector ? [ V a 0 0 V a 1 0 ] and/or at least one second sub-vector ? [ 0 V b 0 0 V b 1 ] , and wherein Va0 and Va1 are elements in the vector Va, and Vb0 and Vb1 are elements in the vector Vb and sending a codebook index to a second network device, wherein the codebook index is associated with the first codebook selected from the first codebook set.

Abstract: A precoding matrix set determining method and apparatus, and a parameter indication information sending method and apparatus are provided. The precoding matrix set determining method include: determining, by a first network device, a parameter used for determining a precoding matrix set, where the parameter includes at least one of a phase parameter, an amplitude parameter, a quantity of vectors in the precoding matrix set, a quantity of vectors in a first codebook set in dual-codebook feedback, and a quantity of vectors in a second codebook set in the dual-codebook feedback, and the parameter is not fixed; and using the parameter to determine the precoding matrix set, where the precoding matrix set includes at least one precoding matrix. By using this solution, flexibility of feeding back a precoding matrix indicator is improved.

Abstract: In a 3D MIMO scenario with 16 antenna ports, antenna ports can be extended in different directions because of different configuration manners of the antenna ports. An apparatus and method where different antenna port counting manners are determined in different configurations are provided, so that in different configurations, a matrix whose dimension is 8 and a matrix whose dimension is 2 are determined in a precoding codebook, and a value of a PMI is fed back to indicate a precoding matrix.

Abstract: A method and an apparatus for measuring and feeding back channel information are disclosed. In an embodiment the method includes receiving, by a first network device, a reference signal and measuring the reference signal to obtain a measurement result. The method further includes selecting a first codebook from a first codebook set according to the measurement result, wherein the first codebook set comprises at least two first codebooks, a sub-vector Wx of each first codebook is formed by a zero vector and a non-zero vector, wherein the vectors forming the Wx correspond to different groups of antenna ports, and sending a codebook index to a second network device, wherein the codebook index corresponds to the first codebook selected from the first codebook set.

Abstract: This application discloses a precoding information sending solution and a precoding information feedback solution. A base station generates a signaling indicator and sends the signaling indicator to user equipment. The signaling indicator indicates related information about a precoding matrix set determined by the base station from a stored codebook, where the precoding matrix set belongs to a subset of the stored codebook. The user equipment selects a precoding matrix according to the signaling indicator sent by the base station, and sends a precoding matrix indicator PMI to the base station. The precoding matrix is selected according to a precoding matrix set and a feedback is performed. Therefore, complexity of searching for the precoding matrix and precoding feedback bits may be reduced.

Abstract: The present invention provides a codebook configuration method and user equipment. The UE receives a reference signal that is of an antenna whose quantity of antenna ports is X and that is sent by a base station and configuration information of a codebook subset restriction for the quantity X of antenna ports, where the configuration information of the codebook subset restriction for the quantity X of antenna ports includes first configuration information and second configuration information; determines, according to the configuration information of the codebook subset restriction for the quantity X of antenna ports, a precoding matrix on which channel measurement and feedback need to be performed; and obtains, by means of measurement according to the reference signal, the precoding matrix on which channel measurement and feedback need to be performed and that is of antenna ports.