摘要:
A method for transmitting signals to reduce feedback overhead and a method for transmitting feedback information for the same are described. In transmitting signals through precoding, different codebook subsets are used in an open-loop transmission mode and a closed-loop transmission mode, thereby reducing feedback overhead. In this case, it is assumed that the codebook subsets for the respective transmission modes are optimized according to each transmission mode.
摘要:
A method for generating a downlink signal in a downlink MIMO (Multiple Input Multiple Output) comprises the steps of: mapping at least one transport block to at least one codeword; mapping at least one layer to each codeword; classifying at least one layer mapped to each codeword into a certain number of layer groups and performing layer permutation by the layer groups; and generating an OFDM (Orthogonal Frequency-Division Multiplexing) symbol using a signal which is permutated by the layer groups. A CRC (Cyclic Redundancy Check) is attached by the layer groups.
摘要:
A method of transmitting a codebook index in a wireless communication system includes receiving a feedback index regarding an entity selected from a plurality of entities belonging to a feedback codebook, selecting a precoder from a precoding codebook using the feedback index, the precoding codebook comprising a plurality of precoders and transmitting a precoder index of the selected precoder. Flexibility can be given to codebook designs, and overhead due to the feedback of codebook indices can be reduced.
摘要:
A method and apparatus for transmitting a signal in a wireless communication system are provided. The method includes: generating R spatial streams each of which is generated on the basis of an information stream and a reference signal; generating N transmit streams on the basis of the R spatial streams and a precoding matrix (where R
摘要:
Methods of controlling a transmission power and configuring a codebook in a multi-antenna system to solve a transmission power unbalance between antennas are disclosed. The method of transmitting data in a multi-antenna system includes (A) transmitting one or more pilot signals within a first symbol region through a first antenna unit, and (B) transmitting one or more pilot signals within a second symbol region through a second antenna unit, wherein data within the first symbol region is transmitted through the second antenna unit, and data within the second symbol region is transmitted through the first antenna unit. According to the present invention, since a transmission power unbalance between antennas is solved, a transmission power can be uniformly assigned to each antenna and channel estimation can be easily performed. Moreover, a power amplifier having a uniform amplification range can be used and designed.
摘要:
A method for a user equipment to precode and transmit an uplink signal efficiently in a 4-antenna system and a method for a base station to receive the transmitted signal efficiently are disclosed. Four antennas of a user equipment can be grouped by a 2-antenna unit. In consideration of this antenna group, it is able to perform precoding using antenna selection/DFT matrix of the antenna group unit. Moreover, a rank-3 codebook can be configured to include a precoding matrix of a type in consideration of power balance per antenna and a precoding matrix including one non-zero component only in one row for maintaining a good CM property.
摘要:
The present invention relates to a radio communication system and more particularly, a method and a device for efficiently transmitting precoded reference signals. The method for transmitting reference signals in multiple antenna transmission, according to one embodiment of the present invention, comprises the steps of: determining a precoding vector for each of M layers (M≧3; M is a natural number); precoding a reference signal for each of the M layers in accordance with said precoding vector; multiplexing the precoded reference signals for N layers (N
摘要:
A method and apparatus for transmitting a signal in a wireless communication system are provided. The method includes: generating R spatial streams each of which is generated on the basis of an information stream and a reference signal; generating N transmit streams on the basis of the R spatial streams and a precoding matrix (where R
摘要:
A method of transmitting precoding information in a multiple antenna system includes selecting M subbands from a plurality of subbands constituting a whole frequency band in a descending order of a channel quality indicator (CQI), where M is an integer satisfying M>0, and transmitting a first precoding matrix indicator (PMI) for the M subbands and a second PMI for a remaining band, wherein the first PMI is a PMI of a codebook selected from a first codebook set including a plurality of codebooks and the second PMI is a PMI of a codebook selected from a second codebook set including a part of the plurality of codebooks of the first codebook set. Accordingly, precoding information can be effectively transmitted by separately preparing a codebook for a best band and a codebook for a non-selected band.
摘要:
A technique for receiving and transmitting downlink reference signals is disclosed. When transmitting downlink data demodulation reference signals (DMRS) (or reference signals for downlink data demodulation) by using two or more layers, the DMRS of each layer may be multiplexed by using a code division multiplexing method and then transmitted. The DMRS for each of the two or more layers may be used for one user equipment or for two or more user equipments. And, downlink control signals for transmitting and receiving such DMRS may be configured to have the same format regardless of a single-user mode (or SU-MIMO mode) or a multi-user mode (or MU-MIMO mode), thereby being used.