Abstract:
Embodiments provide a method for generating a random access channel ZC sequence, and an apparatus. A method for generating a random access channel ZC sequence includes: generating, by a base station, notification signaling, where the notification signaling instructs user equipment UE to generate a random access ZC sequence by using a second restricted set in a random access set; and sending, by the base station, the notification signaling to the UE, so that the UE generates the random access ZC sequence by using the second restricted set, where the random access set includes an unrestricted set, a first restricted set, and the second restricted set; and the second restricted set is a random access set that the UE needs to use when a Doppler frequency shift of the UE is greater than or equal to a first predetermined value.
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 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 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 α is used to perform phase adjustment on φn in W, φn 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, φ n ∈ { e j 2 π 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 α to perform the phase adjustment on φn 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 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:
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 α[V ejφv]T, v=[1 ejθ]; 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:
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:
Embodiments of this application disclose a parameter configuration method and apparatus, relate to the field of communications technologies, and specifically provide a method and an apparatus for setting a resource unit bundling size, to help improve accuracy of a channel estimation result. The method may include: generating parameter configuration signaling, and sending the parameter configuration signaling. The parameter configuration signaling is used to indicate the resource unit bundling size. The resource unit bundling size may be applied to at least two inconsecutive time-frequency resources in frequency domain, and each time-frequency resource includes at least one consecutive resource unit in frequency domain; or may be applied to at least two inconsecutive time-frequency resources in time domain, and each time-frequency resource includes at least one consecutive resource unit in time domain.
Abstract:
The present disclosure relates to methods for feeding back channel state information, user equipment, and base stations. One example 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 is expressed as α[v ejϕv]T, v=[1 ejθ], and sending a precoding matrix indicator (PMI) to the base station, where the PMI corresponds to the selected precoding matrix W.
Abstract:
Embodiments of this application disclose a parameter configuration method and apparatus, relate to the field of communications technologies, and specifically provide a method and an apparatus for setting a resource unit bundling size, to help improve accuracy of a channel estimation result. The method may include: generating parameter configuration signaling, and sending the parameter configuration signaling. The parameter configuration signaling is used to indicate the resource unit bundling size. The resource unit bundling size may be applied to at least two inconsecutive time-frequency resources in frequency domain, and each time-frequency resource includes at least one consecutive resource unit in frequency domain; or may be applied to at least two inconsecutive time-frequency resources in time domain, and each time-frequency resource includes at least one consecutive resource unit in time domain.