Abstract: Embodiments of the present invention provide a method for determining a precoding matrix indicator, a receiving device, and a sending device. The method for determining a precoding matrix indicator includes: selecting, by a receive end, a precoding matrix W from a codebook based on a reference signal sent by a transmit end, where the precoding matrix W is a product of two matrices W1 and W2, where the W1 includes NB block matrices Xi, NB?1, and the W1 is indicated as: W1=diag{X1, . . . , XNB}, where 1?i?NB, and a column xi,j of each block matrix Xi is a Kronecker product of a first vector Aij and a second vector Bij, that is, xij=Aij?Bij; and sending, by the receive end, a precoding matrix indicator PMI corresponding to the precoding matrix W to the transmit end, so that the transmit end obtains the precoding matrix W according to the PMI.

Abstract: A random access method, user equipment, and a network device are provided to reduce interference to a neighboring cell. The method includes: receiving at least two groups of random-access configuration parameters from a network device, where each group of random-access configuration parameters includes a power adjustment step for retransmission of a random access preamble; selecting one group of random-access configuration parameters from the at least two groups of random-access configuration parameters based on a threshold; determining transmit power of the random access preamble based on a power adjustment step for retransmission of the random access preamble in the selected random-access configuration parameters; and sending the random access preamble to the network device at the transmit power.

Abstract: The present disclosure relates to signal transmission methods, network devices, and terminal devices. One example method includes sending, by a network device, N first reference signals to a terminal device, where N is a positive integer greater than or equal to 1, sending, by the network device, physical layer control signaling to the terminal device, where the physical layer control signaling is used to trigger the terminal device to send a channel quality measurement result of the N first reference signals to the network device, and is used to instruct the terminal device to send M second reference signals to the network device, and M is a positive integer greater than or equal to 1, receiving, by the network device, the channel quality measurement result from the terminal device, and receiving, by the network device, the M second reference signals from the terminal device.

Abstract: A signal sending method and apparatus, and a signal receiving method and apparatus are provided, to ensure a low peak-to-average power ratio and a frequency domain diversity gain when a signal is sent on two different subcarrier groups in a same time cell. The method includes: mapping, by a transmit end, a first sequence {pia0, pia1, . . . , piap?1} whose length is P into an ith subcarrier group in M subcarrier groups in a same time cell, where the ith subcarrier group includes K consecutive subcarriers that are evenly distributed, M, P, and K are all greater than or equal to 2, P?K, there is at least one pair of two inconsecutive subcarrier groups in the M subcarrier groups, and a second sequence {pi} corresponding to the M subcarrier groups meets the following requirement: A sequence {xi} is a Barker sequence, where {xi}={xi|x1=ps+1, x2=ps+2, . . . , xM?s=pM,xM?s+1=p1,xM?s+2=p2, . . .

Abstract: This application provides a transmission method, a network device, and a terminal, to save resources. The method includes: determining, by a network device, downlink control information DCI, wherein the DCI includes a first request field, information in the first request field is only used to instruct to send a first reference signal on a first resource, or the information in the first request field is used to instruct to send the first reference signal on the first resource and instruct a terminal to report a measurement result of the first reference signal on the first resource, and the measurement result includes channel state information CSI and/or beam state information BSI; and sending, by the network device, the DCI to the terminal.

Abstract: A method and apparatus for precoding matrix indicator feedback reduce a quantity of bits in the feedback. In the method, a terminal device receive a reference signal from a base station and determines a precoding matrix W in a precoding matrix set corresponding to a rank indication. W satisfies W=W1×W2×W3, where W1, W2 and W3 are matrices and respectively corresponding to a first, second and third precoding matrix indicator. None of W1, W2, and W3 is an identity matrix, and the 2M columns in W1 comprise every column in W1×W2. The terminal device transmits the rank indication, the first precoding matrix indicator, the second precoding matrix indicator, and the third precoding matrix indicator to the base station.

Abstract: The present invention provides a signal sending apparatus, a signal detection apparatus, a signal sending and detection system, a signal sending method, and a signal detection method. The apparatus determines a time unit that is in each time window and that is used to transmit a synchronization signal, and transmits the synchronization signal in the determined time unit in each time window. Therefore, a synchronization signal is always located in a time unit that has a fixed location in each time window, so that a device at a receive end needs to perform detection only in a fixed time unit in each time window, thereby reducing complexity of designing and detecting the synchronization signal.

Abstract: A method and apparatus for precoding matrix indicator feedback reduce a quantity of bits in the feedback. In the method, a terminal device receive a reference signal from a base station, determines a precoding matrix W in a precoding matrix set corresponding to a rank indication. W satisfies W=W1×W2×W3, W1, W2 and W3 and matrices and respectively corresponding to a first, second and third precoding matrix indicator. None of W1, W2, and W3 is an identity matrix, and the 2M columns in W1 comprise every column in W1×W2. The terminal device transmits the rank indication, the first precoding matrix indicator, the second precoding matrix indicator, and the third precoding matrix indicator to the base station. Therefore, a quantity of to-be-selected vectors is reduced by using a first-stage feedback and a second-stage feedback, thereby reducing calculation complexity of third-stage feedback, and reducing a quantity of bits in the third-stage feedback.

Abstract: This application provides a PBCH transmission method and an apparatus. The method includes: receiving, by a terminal device, a PBCH sent by a network device, where the PBCH includes seven most significant bits of an SFN of a radio frame in which the PBCH is located; determining, by the terminal device, a least significant bit of the SFN based on indication information of the least significant bit of the SFN; determining, by the terminal device based on the PBCH, a scrambling code of the PBCH, and determining two remaining bits of the SFN based on a one-to-one correspondence between the two remaining bits of the SFN and the scrambling code of the PBCH; and determining, by the terminal device, the SFN of the radio frame in which the PBCH is located.

Abstract: An embodiment of the present invention discloses a power control method, including: obtaining, by a UE, configuration information, where the configuration information includes a configuration parameter of at least one Scell configured by a base station for the UE; setting, by the UE, an initial power adjustment value of the Scell according to the configuration parameter of the Scell in the configuration information; and controlling, by the UE, transmit power on the Scell according to the set initial power adjustment value of the Scell. Correspondingly, an embodiment of the present invention further discloses an activation management method, a UE, and a base station. By using the present invention, transmit power of a UE on an Scell can be accurately controlled, thereby ensuring accuracy of data transmission.

Abstract: The present invention provides a method for transmitting a pilot signal, a base station, and user equipment The method including: determining, by a base station, a transmission period of a pilot antenna port group; and sending, by the base station, in a transmission period corresponding to each pilot antenna port group, a pilot signal to user equipment by using a resource corresponding to the pilot antenna port group, so that the user equipment measures channel quality according to the pilot signal. By means of the technical solutions provided in the embodiments of the present invention, pilot signal overheads can be reduced.

Abstract: This application discloses a synchronization signal sending method and a related device. The method includes: generating a first synchronization signal sequence and a second synchronization signal sequence, where the first synchronization signal sequence is a sequence obtained based on a first m-sequence, the second synchronization signal sequence is a sequence obtained based on a Gold sequence, the Gold sequence is generated based on a second m-sequence and a third m-sequence, and a generator polynomial of the first m-sequence is the same as a generator polynomial of the second m-sequence; mapping the first synchronization signal sequence onto M subcarriers in a first time unit to obtain a first synchronization signal, and mapping the second synchronization signal sequence onto M subcarriers in a second time unit to obtain a second synchronization signal, where M and N are positive integers greater than 1.

Abstract: This application discloses a reference signal configuration method and apparatus. Before a network device sends reference signals aperiodically, the network device sends configuration information to a terminal device, where the configuration information is used to indicate a timeslot offset of one or more reference signal resource sets. Therefore, the network device can flexibly send reference signals in different timeslots, thereby reducing a quantity of times of reference signal triggering and measurement result reporting, and improving efficiency of a communications system.

Abstract: Embodiments of this application provide a signal transmission method and apparatus. The method includes: determining, by a network device, a reference signal resource pool; sending, by the network device, indication information to a terminal device; sending, by the network device, first configuration information and/or second configuration information to the terminal device based on the reference signal resource pool; and sending, by the network device, the first-type reference signal to the terminal device based on the first configuration information, and/or sending, by the network device, the second-type reference signal to the terminal device based on the second configuration information. By using the signal transmission method and apparatus in the embodiments of this application, resources used for different types of reference signals can be allocated flexibly, thereby improving resource utilization.

Abstract: This application provides an uplink reference signal sending method and apparatus, a base station, and user equipment (UE). The method includes: configuring, by the base station, M pieces of uplink reference signal resource information for the UE; and sending, by the base station, the M pieces of uplink reference signal resource information to the UE, so that the UE sends uplink reference signals based on different uplink reference signal resource information with different beamforming gains. A path loss is compensated for by using a beamforming technology. In addition, the base station configures the M pieces of uplink reference signal resource information for the user equipment UE, so that the UE sends the uplink reference signals by using different relatively uplink reference signal resource information based on different beamforming gains. Therefore, uplink reference signal sending efficiency is improved.

Abstract: This application relates to a method, includes: determining, by a terminal, a first initial transmit power and a second initial transmit power; receiving minimum guaranteed power information that is of channels carried by the first carrier and that is sent by an access network device; and obtaining an available transmit power for channels that are transmitted in N first subframes and that are carried by the first carrier and an available transmit power of a channel that is transmitted in a second subframe and that is carried by a second carrier.

Abstract: This application provides a PBCH transmission method and an apparatus. The method includes: receiving, by a terminal device, a PBCH sent by a network device, where the PBCH includes seven most significant bits of an SFN of a radio frame in which the PBCH is located; determining, by the terminal device, a least significant bit of the SFN based on indication information of the least significant bit of the SFN; determining, by the terminal device based on the PBCH, a scrambling code of the PBCH, and determining two remaining bits of the SFN based on a one-to-one correspondence between the two remaining bits of the SFN and the scrambling code of the PBCH; and determining, by the terminal device, the SFN of the radio frame in which the PBCH is located.

Abstract: The present disclosure describes a physical downlink control channel (PDCCH) candidate determining method and device, and relates to the field of wireless communications, so as to avoid PDCCH blocking and improve reliability of control information transmission. The method of the present invention includes: determining an PDCCH resource set p in a subframe k, where the PDCCH resource set p includes NECCE,p,k=q×r enhanced control channel elements (ECCEs), an PDCCH candidate of an PDCCH with an aggregation level being L corresponds to L ECCEs having consecutive reference numerals, and an PDCCH candidate is capable of carrying an PDCCH; and determining the number of PDCCH candidates at the aggregation level L of a carrier corresponding to an index Cellindex and an ECCE corresponding to each PDCCH candidate, where the ECCE corresponding to each PDCCH candidate at the aggregation level L is related to the index Cellindex.

Abstract: Embodiments of this application provide a signal communication method and apparatus. The method includes: sending, by a network device, a channel quality threshold to a terminal device, where the channel quality threshold is used by the terminal device to report first channel quality information, and the channel quality threshold is a threshold of second channel quality information; and receiving, by the network device, a first quantity of pieces of the first channel quality information sent by the terminal device based on the channel quality threshold.

Abstract: In a system and method of control channel transmission in the communications field, REs, except those used for transmitting a DMRS, are grouped in each physical resource block pair of L physical resource block pairs. The L physical resource block pairs are determined to be used to transmit a control channel into N eREGs. The number of valid REs are calculated except other overheads in each eREG of the N eREGs. Each of the eCCEs are mapped onto M eREGs according to the number of valid REs included in each eREG of the N eREGs of each physical resource block pair. The eCCE is sent in the REs included in the eREG.