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.

Abstract: The present invention discloses a channel state information feedback method and apparatus. User equipment determines a PMI and a CQI, and a feedback expression manner of the PMI and the CQI, where the feedback expression manner includes a first or a second feedback expression manner, and sends the PMI and the CQI to a network device in the determined feedback expression manner of the PMI and the CQI, where the first feedback expression manner includes: using T CQI values to express CQI of M codewords, and using one PMI value to indicate one PMI, where T is less than M, and there is at least one CQI value that can express CQI of at least two codewords; and the second feedback expression manner includes: using M CQI values to express CQI of M codewords. The present invention may be applied to a scenario in which an antenna quantity increases.

Abstract: The present invention discloses a method for feeding back channel state information, a method for receiving channel state information, and a device. The method includes: selecting, by a terminal, a precoding matrix from a preset codebook subset for each subband in N subbands according to a configured reference signal, where each precoding matrix in the codebook subset is identified by a first PMI, a second PMI, and a third PMI that is used to indicate a phase relationship, first PMIs corresponding to the precoding matrices selected by the terminal for all subbands in the N subbands are the same, the precoding matrix selected for each subband in the N subbands corresponds to one second PMI, and third PMIs corresponding to the precoding matrices for all subbands in the N subbands are the same; and reporting, by the terminal, the first PMI, the second PMI, and the third PMI.

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 signal transmission method and a network device. The signal transmission method includes: sending, by a first network device, a first signal before performing cell selection; and sending, by the first network device, a second signal after performing cell selection, where resources used by the first network device to send the first signal and the second signal are different, and the second signal is a random access signal.

Abstract: The present invention provides a precoding matrix indicator feedback method, a receive end, and a transmit end. The method includes: selecting, by a receive end based on a reference signal, a precoding matrix W from a codebook, where a coefficient ? is used to perform phase adjustment on ?n in W, ?n represents a phase difference between weighted values of a first antenna group and a second antenna group of a transmit end for a transmission signal from a same transmission layer, ? n ? { e j ? ? 2 ? ? ? ? ? n Q } , and the first antenna group and the second antenna group belong to a same multi-antenna system; and sending, by the receive end, a precoding matrix indicator (PMI) to the transmit end. In this way, using the coefficient ? to perform the phase adjustment on ?n can increase a size of a codebook set applicable to different antenna configurations, and improve precision of the receive end to feed back a PMI.

Abstract: A wireless access method and apparatus, the method including sending N first signal sets on N first resources, where N is an integer greater than 1, receiving Z response signals from a terminal for the N first signal sets, where each response signal of the response signals comprises indication information of a resource on which the respective first signal set of the N first signal sets is located, Z is an integer greater than or equal to 1, and Z is less than or equal to N, and sending M second signal sets on M second resources according to the Z response signals, where M is an integer greater than or equal to 1, and each second signal set of the M second signal sets corresponds to at least one of the N first signal sets.

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: The present invention relates to the communications field, and provides a channel measurement method, a base station, and UE, to perform channel measurement without affecting downlink data transmission. The method includes: obtaining, by UE, a reference signal resource mapping diagram, and obtaining a reference signal according to the reference signal resource mapping diagram; performing, by the UE, channel measurement according to the reference signal to determine channel state information, and feeding back the channel state information to a base station, where the reference signal resource mapping diagram is a location to which a time-frequency resource of the reference signal is mapped, the reference signal resource mapping diagram is a first reference signal resource mapping diagram or a second reference signal resource mapping diagram.

Abstract: Embodiments of the present invention relate to the field of communications technologies, and disclose a CSI measurement and feedback method and a device, so as to resolve a prior-art problem that flexibility is poor when the UE measures a measurement pilot and provides a feedback. In a specific solution, a first network device sends a first signal to a second network device. The first signal is used for the second network device to determine a first measurement pilot according to the first signal, and send the first measurement pilot to the first network device. The first network device receives the first measurement pilot sent by the second network device, and measures the first measurement pilot to obtain first CSI. The first CSI includes at least one of a CQI, a PMI, an RI, or port selection information.

Abstract: A control information sending method, a base station, and user equipment are provided. The method includes: sending, by a base station, first control information to first user equipment; transceiving, by the base station, first data to/from the first user equipment according to the first control information; and sending, by the base station, first trigger information to the first user equipment, where the first trigger information is used to indicate that the base station transceives second data to/from the first user equipment according to partial information or all information of the first control information.

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: Embodiments of the present invention provide a signal transmission apparatus, system, and method. A first network device detects, in a first resource group, a first signal sent by a second network device, and the first network device determines an mth resource in a second resource group according to an nth resource in the first resource group and a first correspondence.

Abstract: Embodiments disclose a method for transmitting a 4-antenna precoding matrix, a user equipment, and a base station. The method includes determining a rank used for indicating the number of transmission layers, determining a first precoding matrix in a codebook set corresponding to the rank, determining a first PMI and a second PMI used for indicating the first precoding matrix, and sending the first PMI and the second PMI used for indicating the first precoding matrix to a base station.

Abstract: A method for measuring and feeding back channel information and a corresponding apparatus are provided. A first network device receives a reference signal, measures the reference signal to obtain a measurement result, and selects a first codebook from a first codebook set according to the measurement result; for different sub-vectors Wx (1) and Wx (2), a location of a non-zero vector in the Wx (1) is the same as a location of a non-zero vector in the Wx (2); and formation according to different structures is: for different sub-vectors Wx (1) and Wx (2), a location of a non-zero vector in the Wx (1) is different from a location of a non-zero vector in the Wx (2); and the first network device sends a codebook index to a second network device, where the codebook index corresponds to the first codebook selected from the first codebook set.

Abstract: The present invention discloses a data transmission method and device. The method includes: separately configuring, by an eNodeB in different time units on a specific frequency band according to a TDD mode or an FDD mode, an uplink frequency resource used for transmitting uplink data and a downlink frequency resource used for transmitting downlink data; and sending, by the eNodeB, downlink data to user equipment UE by using the configured downlink frequency resource, and receiving, by using the configured uplink frequency resource, uplink data sent by the UE, so that an uplink frequency resource and a downlink frequency resource are configured in different time units on a same frequency band according to both a TDD mode and an FDD mode.

Abstract: Embodiments disclose a method for transmitting a 4-antenna precoding matrix, a user equipment, and a base station. The method includes determining a rank used for indicating the number of transmission layers, determining a first precoding matrix in a codebook set corresponding to the rank, determining a first PMI and a second PMI used for indicating the first precoding matrix, and sending the first PMI and the second PMI used for indicating the first precoding matrix to a base station.