Methods, systems, and devices for wireless communications are described. A user equipment (UE) may determine that a base station has scheduled the UE for one or more downlink transmissions, each of the one or more downlink transmissions having an associated repetition factor that corresponds to one of a plurality of configured repetition factors configured at the UE. The UE may identify an applied repetition factor to apply to feedback codebook generation for the one or more downlink transmissions. The UE may generate a feedback codebook for reporting feedback for the one or more downlink transmissions, the feedback codebook populated based at least in part on the applied repetition factor and on whether the one or more downlink transmissions were successfully received and decoded. The UE may transmit to the base station a feedback report that includes the feedback codebook.

Dynamic reconfiguration of CSI-RS resources for CSI reporting is described for full dimension multiple input, multiple output (FD-MIMO) systems. While a larger number of channel state information (CSI) reference signal (CSI-RS) resources with independent resource configuration are configured and associated with a CSI process, only a subset of resources that are activated by additional signaling are used for CSI measurement and reporting. The set of activated CSI-RS resources may include only a single CSI-RS resource. Both periodic and aperiodic CSI reporting may then be based on the same set of the activated CSI-RS resources. Medium access control (MAC) control elements may be used to provide activation/deactivation of the CSI-RS resources. Additionally, CSI reporting may be based on both the activated CSI-RS resources and the associated number of antenna ports.

A codebook configuration method, a port configuration method and a device for the same are provided. A communication device determines configuration information of a codebook, where the configuration information of the codebook includes at least one of value range selection information of a base vector in a construction model of the codebook or value range selection information of a codeword in the codebook. The communication device sends the configuration information of the codebook to a communication peer end.

A method for operating a user equipment (UE) comprises receiving a configuration about a CSI report, the configuration including information about a codebook, the codebook comprising components: (i) sets of basis vectors including a first set of vectors each of length P.sub.CSIRS×1 for a SD, a second set of vectors each of length N.sub.3×1 for a FD, and a third set of vectors each of length N.sub.4×1 for a DD, and (ii) coefficients associated with each basis vector triple (a.sub.i,b.sub.f,c.sub.d), a.sub.i from the first set, b.sub.f from the second set, and c.sub.d from the third set; determining, based on the configuration, the components; and transmitting the CSI report including: at least one basis vector indicator indicating all or a portion of the sets of basis vectors, and at least one coefficient indicator indicating all or a portion of the coefficients.

The present application relates to communication technology. Disclosed are a channel reciprocity-based precoding matrix configuration method and apparatus. The method comprises: in downlink transmission, a network side separately sends, on each antenna port associated with each transmission layer, a CSI-RS subjected to beamforming to a terminal by using beams calculated according to angle information and delay information determined on the basis of uplink channel state information, and determines a precoding matrix for downlink transmission of the terminal according to beams sent on K0 antenna ports selected by the terminal on the basis of the CSI-RS, and a beam combination coefficient set. In this way, both angle information reciprocity and delay information reciprocity between uplink and downlink channels can be used to directly calculate formed beams for transmitting the CSI-RS, without performing SVD calculation for effective channel information of each PMI subband, thereby reducing the calculation complexity of the terminal, reducing the feedback overhead of the terminal, and also improving system performance.

A communication device for providing a channel state information, CSI, feedback in a wireless communication system includes a transceiver to receive a radio signal including downlink reference signals. The processor estimates an explicit CSI, selects a Doppler-delay precoder matrix for a composite Doppler-delay-beam three-stage precoder, calculates and reports to the transmitter a CSI feedback. The communication device selects from one or more codebooks a subset of D delay components and/or a subset of F Doppler-frequency components and uses the selected subset of delay components for each polarization and each spatial beam and/or the selected subset of Doppler-frequency components for each polarization, each spatial beam and each delay, when calculating the Doppler-delay precoder matrix.

A base station includes a transmit path circuitry to transmit an indication of whether a subscriber station is configured with precoding matrix indicator/rank indicator (PMI/RI) reporting. The transmit path circuitry sets a pre-coding granularity to multiple physical resource blocks in the frequency domain to perform a same pre-coding over a bundled resource block if the subscriber station is configured with PMI/RI reporting. The bundled resource block includes multiple consecutive physical resource blocks in the frequency domain. The base station also includes a receive path circuitry to receive feedback from the subscriber station.

Provided is a precoding method for generating, from a plurality of baseband signals, a plurality of precoded signals to be transmitted over the same frequency bandwidth at the same time, including the steps of selecting a matrix F[i] from among N matrices, which define precoding performed on the plurality of baseband signals, while switching between the N matrices, i being an integer from 0 to N−1, and N being an integer at least two, generating a first precoded signal z1 and a second precoded signal z2, generating a first encoded block and a second encoded block using a predetermined error correction block encoding method, generating a baseband signal with M symbols from the first encoded block and a baseband signal with M symbols the second encoded block, and precoding a combination of the generated baseband signals to generate a precoded signal having M slots.

A method for estimating a channel status by a base station in a wireless communication system according to an embodiment of the present invention comprises the steps of: obtaining an uplink channel matrix by using a sounding reference signal (SRS) received from a terminal; transmitting a channel state information-reference signal (CSI-RS) through at least some antenna devices in a two-dimensional antenna array of the base station; receiving a channel quality indicator (CQI) calculated on the basis of the CSI-RS transmission; and obtaining, through a predetermined correction factor obtained on the basis of the CQI and the uplink channel matrix, a downlink channel matrix for the entire two-dimensional antenna array comprising the remaining antenna devices through which the CSI-RS is not transmitted.

Two-way (full-duplex) wireless links in facilitating network management and improve network performance. Once aspect includes methods for network management using a high-throughput channel and a low-throughput channel. Other aspects include methods to facilitate practical realization and improve performance of some of the network information theoretic configurations, such as Space-Division Multiple Access (SDMA) in uplink and downlink, Interference Channel, and other forms of distributed collaborative signaling schemes. Another aspect includes methods to support cognitive wireless networks.