Methods and apparatuses for CSI reporting mechanisms are provided. A user equipment (UE) includes a transceiver and a processor operably connected to the transceiver. The transceiver is configured to receive configuration information including a channel state information (CSI) process, a first multiple-input multiple-output (MIMO) Type, and a second MIMO Type. The processor is configured to calculate and report, in response to receipt of the configuration information, a CSI for each of the first and second MIMO Types. The second MIMO Type is Class B and is associated with a single non-zero-power CSI reference signal (NZP CSI-RS) resource that includes at most 8 antenna ports.

An embodiment of a transmitter includes a first number of antennas and a signal generator. The antennas are each spaced from another of the antennas by approximately a distance, and are configured to provide, at one or more wavelengths that are greater than twice the distance, a channel capacity that exceeds a saturation channel capacity. The signal generator is configured to generate a second number of signals each having a wavelength that is greater than twice the distance, the second number being related to a third number of signal pipes. And the signal generator is configured to couple each of the signals to a respective one of the antennas. Such a transmitter can be a multiple-input-multiple-output orthogonal-frequency-division-multiplexing (OFDM-MIMO) transmitter that can be configured to increase the information-carrying capacity of a channel (i.e., increase the channel capacity) above and beyond a saturation capacity of the channel.

An embodiment of a receiver includes a first number of antennas and a signal analyzer. The antennas are each spaced from another of the antennas by approximately a distance, and are configured to provide, at one or more wavelengths that are greater than twice the distance, a channel capacity that exceeds a saturation channel capacity. The signal analyzer is configured to recover information from a second number of signals each received by at least one of the antennas over a respective one of a third number of signal pipes, and each having a wavelength that is greater than twice the distance, the second number being related to the third number. Such a receiver can be a multiple-input-multiple-output orthogonal-frequency-division-multiplexing (OFDM-MIMO) receiver that can be configured to increase the information-carrying capacity of a channel (i.e., increase the channel capacity) above and beyond a saturation capacity of the channel.

Embodiments of the present invention provide a data transmission method for a multi-antenna system, and a device. The method includes: performing first precoding processing on to-be-sent data in a first antenna direction of a multi-antenna system to generate first data; performing second precoding processing on the first data in a second antenna direction of the multi-antenna system to generate second data; and sending the second data to a receive node through each antenna port of the multi-antenna system; wherein: when the first precoding processing is first transmit diversity processing, the second precoding processing is second transmit diversity processing or second transmit spatial multiplexing processing; when the first precoding processing is first transmit spatial multiplexing processing, the second precoding processing is second transmit diversity processing. The method and the device are used to send data by using antennas in multiple antenna directions in the multi-antenna system.

Disclosed is a precoding method comprising the steps of: generating a first coded block and a second coded block with use of a predetermined error correction block coding scheme; generating a first precoded signal z1 and a second precoded signal z2 by performing a precoding process, which corresponds to a matrix selected from among the N matrices F[i], on a first baseband signal s1 generated from the first coded block and a second baseband signal s2 generated from the second coded block, respectively; the first precoded signal z1 and the second precoded signal z2 satisfying (z1, z2).sup.T=F[i] (s1, s2).sup.T; and changing both of or one of a power of the first precoded signal z1 and a power of the second precoded signal z2, such that an average power of the first precoded signal z1 is less than an average power of the second precoded signal z2.

Some wireless communication networks may improve communication reliability and/or throughput using multiple-input, multiple-output (MIMO) schemes. MIMO operation may in turn be supported by the use of channel state information reference signals (CSI-RS), which may allow communicating devices to estimate and leverage multipath channel conditions. However, the signaling used to support such communications may consume significant resources. In accordance with the described techniques, a user equipment (UE) may identify non-zero-power beams based on received CSI-RS. The non-zero-power beams may contribute to the final precoding vector. Rather than transmitting beam coefficients relating to zero-power beams, the UE may instead indicate a presence of these zero-power beams to the base station (e.g., by indicating a number of non-zero-power beams). Such techniques may reduce overhead of the communications or otherwise benefit the system.

Certain aspects of the present disclosure provide techniques for a basis report for compressed channel state information (CSI) feedback with a non-contiguous subband configuration. A method for wireless communication by a user equipment (UE) includes receiving a CSI report configuration configuring the UE for reporting precoding matrix information including, a plurality of selected beams, a frequency domain compression matrix for each of the beams at each of a plurality of taps in the time domain, and a subset of a plurality of linear combination coefficients associated with the frequency domain compression matrices and beams. The UE receives a configuration of non-contiguous frequency resources for CSI reporting. The UE may perform frequency domain compression of the precoding matrix information using a truncated frequency domain compression matrix or performing separate frequency domain compression of the precoding matrix information for each set of contiguous frequency resources.

Various systems and methods disclosed herein describe improvements for beam management that leverage virtualization across a vertical polarization (V-Pol) and horizontal polarization (H-Pol). One or more of a user equipment (UE) and a base station may include an antenna array comprising V-Pol antenna elements and H-Pol antenna elements. The UE may determine a number of receive (Rx) beam of an Rx beam sweep are needed, signal this number to the base station, and perform the beam sweep according to one or both of the V-Pol and H-Pol. A UE may use group based beam reporting to indicate to the base station a transmit (Tx) beam upon which downlink MIMO using V-Pol and H-Pol may be supported by reporting a same transmission configuration indication (TCI) corresponding to the Tx beam for both a first Rx beam and a second Rx beam in a group based beam reporting message.

Various systems and methods disclosed herein describe improvements for beam management that leverage virtualization across a vertical polarization (V-Pol) and horizontal polarization (H-Pol). One or more of a user equipment (UE) and a base station may include an antenna array comprising both V-Pol and H-Pol antenna elements. A UE may message a base station to configure uplink (UL) multiple input multiple output (MIMO) operations across one or more of the V-Pol and the H-Pol. The message may include a number of MIMO layers to be concurrently used for communicating data to the base station, where each MIMO layer is transmitted using one of a V-Pol and an H-Pol; a number of sounding reference signals (SRS) to be transmitted by the UE, each SRS to be transmitted using one of the V-Pol and the H-Pol; and a supported maximum number of antenna ports per each SRS.

Methods, systems, and devices for wireless communications are described for implementation of higher rank transmissions (e.g., higher rank line of sight (LOS) schemes) over a given beam direction associated with a selected transmission configuration indicator (TCI) state. According to some aspects, expanded antenna arrays, spatial separation (e.g., distance) between antenna elements, lower carrier frequencies (e.g., associated with frequency range 4 (FR4) systems), etc. may be leveraged to communicate uncorrelated signals (e.g., independent streams across spatial layers) for higher rank transmissions using a given TCI state (e.g., using a single beam direction). Various aspects of the described techniques may provide for higher rank directional communications by a user equipment (UE) (e.g., via uncorrelation in a single UE), higher rank directional communications by select UEs (e.g., via uncorrelation across specific UEs), base station antenna selection for uncorrelation at multiple served UEs, etc.