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 method and apparatus for allowing a UE to transmit uplink signals using a MIMO scheme are disclosed. In order to maintain good Peak power to Average Power Ratio (PAPR) or Cubic Metric (CM) properties when the UE transmits uplink signals using the MIMO scheme, the UE uses a precoding scheme based on a precoding matrix established in a manner that one layer is transmitted to each antenna in specific rank transmission.

A method and apparatus for allowing a UE to transmit uplink signals using a MIMO scheme are disclosed. In order to maintain good Peak power to Average Power Ratio (PAPR) or Cubic Metric (CM) properties when the UE transmits uplink signals using the MIMO scheme, the UE uses a precoding scheme based on a precoding matrix established in a manner that one layer is transmitted to each antenna in specific rank transmission.

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.

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 stochastic channel state information transmission/reception method and apparatus is provided for use in a multiuser radio communication system. The signal method of transmitting and receiving signals in a terminal in a mobile communication system according to the present disclosure includes receiving a reference signal transmitted by a base station, estimating channel information based on the reference signal, predicting a channel estimation error based on the channel information, generating feedback information based on the channel estimation error, and transmitting feedback information to the base station.

A stochastic channel state information transmission/reception method and apparatus is provided for use in a multiuser radio communication system. The signal method of transmitting and receiving signals in a terminal in a mobile communication system according to the present disclosure includes receiving a reference signal transmitted by a base station, estimating channel information based on the reference signal, predicting a channel estimation error based on the channel information, generating feedback information based on the channel estimation error, and transmitting feedback information to the base station.

Technique for full-duplex transmission in many-antenna multi-user (MU) multiple-input multiple-output (MIMO) systems is presented in this disclosure. An estimate of a self-interference channel between a plurality of transmit antennas and a plurality of receive antennas is first obtained. A precoder for self-interference reduction is generated based on minimizing a self-interference power related to the self-interference channel that is present at the plurality of receive antennas. Transmission data are modified using the precoder by projecting the transmission data onto a defined number of singular vectors of the self-interference channel that correspond to the defined number of smallest singular values of the self-interference channel. Data are received in full-duplex mode via the plurality of receive antennas simultaneously with transmitting the modified transmission data.

Technique for full-duplex transmission in many-antenna multi-user (MU) multiple-input multiple-output (MIMO) systems is presented in this disclosure. An estimate of a self-interference channel between a plurality of transmit antennas and a plurality of receive antennas is first obtained. A precoder for self-interference reduction is generated based on minimizing a self-interference power related to the self-interference channel that is present at the plurality of receive antennas. Transmission data are modified using the precoder by projecting the transmission data onto a defined number of singular vectors of the self-interference channel that correspond to the defined number of smallest singular values of the self-interference channel. Data are received in full-duplex mode via the plurality of receive antennas simultaneously with transmitting the modified transmission data.

Various aspects of the present disclosure generally relate to wireless communication. A wireless communication device may have an apparatus that aligns the non-linearity between transmit chains of the wireless communication device that are driven by the same digital port. The apparatus may adjust an amplification power out or an amplification saturated power to adjust a ratio between the amplification saturated power and the amplification power out for one or more transmit chains of the wireless communication device. The apparatus may adjust the ratios of transmit chains to align the ratios of the transmit chains for more consistent management of non-linear characteristics of the chain components. Numerous other aspects are described.