摘要:
The embodiments of the present invention disclose a method and an apparatus for sub-sampling of a codebook in the LTE-A system where a precoding matrix W is a product of two matrices W1 and W2, i.e. W=W1W2, codebooks for W, W1 and W2 are denoted as C, C1 and C2 respectively, and r indicates a rank. The method includes sub-sampling the codebook C such that the sub-sampled codebook C has a size of equal to or less than 4 bits. In the sub-sampling, codewords evenly distributed in the codebook C are extracted, where some or all of the codewords are in a form of discrete Fourier transform (DFT) vector to be suitable for evenly linear arrays, and the other codewords are suitable for cross-polarized linear arrays.
摘要:
A method for determining precoding matrix for the sub-band precoding in a transmitter with M transmitting antennas. The method includes determining an optimized first matrix W1 according to wideband and/or long-term channel properties, multiplying the optimized first matrix W1, with each second matrix W2, in a second codebook, to obtain a plurality of candidate precoding matrices, the second matrix W2 corresponds to frequency-selective and/or short-term channel properties; selecting an optimized one from the plurality of candidate preceding matrices for precoding the data to be transmitted, according to a frequency selection and/or a short-term channel state information. The amount of DFT beams may be increased to improve the spatial resolution; a diagonal matrix is involved in the first matrix W1; and phase adjustment is involved in the second matrix W2, so as to guarantee the adjusted phase is evenly distributed among the whole phase space.
摘要:
A method for determining precoding matrix for the sub-band precoding in a transmitter, wherein the transmitter has M transmitting antennas, and the method comprises: a. determining an optimized first matrix W1 according to wideband and/or long-term channel properties, with the first matrix W1 corresponding to wideband and/or long-term channel properties; b. multiplying the optimized first matrix W1, with each second matrix W2, in a second codebook, so as to obtain a plurality of candidate precoding matrices, the second matrix W2 corresponds to frequency-selective and/or short-term channel properties; c. selecting an optimized one from the plurality of candidate preceding matrices for precoding the data to be transmitted, according to a frequency selection and/or a short-term channel state information; characterized in that, the amount of DFT beams is increased to improve the spatial resolution; a diagonal matrix is involved in said first matrix W1; and phrase adjustment is involved in said second matrix W2, so as to guarantee the adjusted phrase is evenly distributed among the whole phrase space.
摘要:
The present invention provides a precoding method for a cross-polarized antenna array, the cross-polarized antenna array comprising a first group of coplanar polarized antennas and a second group of coplanar polarized antennas, the method comprising the following steps: generating, for at least one layer of data stream, a feedback codebook comprising a plurality of codewords; receiving a selection of the codeword in the feedback codebook; determining a corresponding codeword from the feedback codebook according to the received selection; generating a precoding matrix based on the determined codeword to precode the at least one layer of data stream; wherein each codeword in the feedback codebook comprises a first coefficient portion corresponding to a first group of coplanar polarized antennas and a second coefficient portion corresponding to the second group of coplanar polarized antennas, and there is a complex scaling relation between the coefficients in the first coefficient portion and the second coefficient portion corresponding to the same layer of data stream. Correspondingly, the present invention further provides a precoder for a cross-polarized antenna array.
摘要:
Embodiments of the present invention generally relate to a method and system of channel feedback in wireless communications. Specifically, according to embodiments of the present invention, there is provided a two-stage Co MP feedback mechanism, such that different types of channel feedback are transmitted in each stage. Specifically, during the first stage, information regarding long-term features and/or wideband features of a channel is fed back; while during the second stage, information regarding short-term features and/or narrow features of channel is fed back. The first stage and the second stage may be periodically repeated. The information fed back during the first and second stages are used to calculate feedback information characterizing a joint-channel feature. In this way, overheads associated with channel feedback may be effectively reduced. Corresponding methods and apparatuses are also disclosed.
摘要:
The present invention provides a precoding method for a cross-polarized antenna array, the cross-polarized antenna array comprising a first group of coplanar polarized antennas and a second group of coplanar polarized antennas, the method comprising the following steps: generating,for at least one layer of data stream,a feedback codebook comprising a plurality of code-words; receiving a selection of the codeword in the feedback codebook; determining a corresponding codeword from the feedback codebook according to the received selection; generating a precoding matrix based on the determined codeword to precode the at least one layer of data stream; wherein each codeword in the feedback codebook comprises a first coefficient portion corresponding to a first group of coplanar polarized antennas and a second coefficient portion corresponding to the second group of coplanar polarized antennas, and there is a complex scaling relation between the coefficients in the first coefficient portion and the second coefficient portion corresponding to the same layer of data stream. Correspondingly, the present invention further provides a precoder for a cross-polarized antenna array.
摘要:
The present invention discloses a method and apparatus for improving the accuracy of transmitting CSI via PUCCH. The method for improving the accuracy of transmission of channel status information via the physical uplink control channel comprises reducing the number of bits of other channel information transmitted via the physical uplink control channel under the condition that the payload of the physical uplink control channel remains unchanged, and utilizing the thus-saved bits to transmit the channel state information to reduce the degree of sub-sampling the channel state information and thereby improve the accuracy of transmission of the channel status information via the physical uplink control channel. According to the present invention, system performance loss can be reduced.
摘要:
The embodiments of the present invention disclose a method and an apparatus for sub-sampling of a codebook in the LTE-A system where a precoding matrix W is a product of two matrices W1 and W2, i.e. W=W1W2, codebooks for W, W1 and W2 are denoted as C, C1 and C2 respectively, and r indicates a rank. The method includes sub-sampling the codebook C such that the sub-sampled codebook C has a size of equal to or less than 4 bits. In the sub-sampling, codewords evenly distributed in the codebook C are extracted, where some or all of the codewords are in a form of discrete Fourier transform (DFT) vector to be suitable for evenly linear arrays, and the other codewords are suitable for cross-polarized linear arrays.
摘要:
A mobile terminal is provided in the present invention, comprising: a channel state information feedback calculating unit configured to calculate a channel state information feedback between the mobile terminal and a serving cell of the mobile terminal and those between the mobile terminal and all cooperating cells; a channel quality information feedback calculating unit configured to calculate a channel quality information feedback for the serving cell of the mobile terminal; and a transmission unit configured to transmit the channel state information feedbacks and the channel quality information feedback to the serving cell. The present invention greatly improves the performance of a LTE-A system and greatly reduces feedback overhead. The present invention is a scalable feedback solution and may be flexibly applied to various coordinated multipoint transmission scenarios.
摘要:
A method and apparatus for generating a codebook and the associated data in a network device are provided in the invention. The method comprises the steps of generating a first row sub-matrix corresponding to a first group of antennas respectively for the respective ranks of the codebook to be generated; generating a second row sub-matrix corresponding to a second group of antennas respectively for the respective ranks based on an amount of the phase adjustment of the second group of antennas with respect to the first group of antennas; and generating a second codebook in accordance with the first row sub-matrix and the second row sub-matrix. As some embodiments of the method of the invention comprise the implementation of adjustment of the phase offset and the amplitude difference between the first and the second groups of antennas, the phase offset and the relative amplitude difference among the cross-polarized linear antennas array is guaranteed when the network device uses the downlink data generated therefore for transmission, such that the receiving quality of the transmitted data may be improved, and the system performance may be improved effectively.