Abstract: Systems, methods, and instrumentalities are disclosed herein for pre-processing for channel state information (CSI) compression in wireless system. A WTRU may receive configuration information that indicates a reference signal and a data processing model for channel state information (CSI) compression. The WTRU may determine CSI associated with a channel using the reference signal. The WTRU may determine a channel condition associated with pre-processing. The WTRU may select a pre-processing type from a plurality of pre-processing types based on the data processing model and the determined channel condition associated with pre-processing. The WTRU may pre-process the CSI associated with the channel based on the selected pre-processing type. The WTRU may generate compressed CSI by compressing the pre-processed CSI using the data processing model for CSI compression. The WTRU may send the compressed CSI to a network.

Abstract: Methods and apparatuses for controlling a reconfigurable intelligent surface (RIS) to generate one or more modulated symbols may be described herein. The processor may be configured to generate an amplitude of the modulated symbol(s) by activating one or more of the plurality of portions of the RIS. The processor may be configured to generate a phase of modulated symbol(s) by controlling one or more phase shifts applied by one or more activated portions of the RIS. The method may include transmitting the one or more modulated symbols using the RIS. The method may include a RIS-based joint beamforming and/or modulation scheme with low PAPR. The RIS may be divided into one or more portions for attaining various gains. The RIS may be divided into an In-phase and/or Quadrature branches. The method may include an Amplitude-phase shift keying (A-PSK) and/or Quadrature amplitude-phase shift keying (AQ-PSK) joint beamforming and/or modulation scheme(s).

Abstract: Procedures, methods, architectures, apparatuses, systems, devices, and computer program products directed to adaptive reference signal configuration are described. A method for adapting a reference signal configuration may be implemented in a WTRU. For example, the WTRU may receive a transmission e.g., from a base station according to one or more first reference signal configurations. For example, a channel estimation measurement may be performed for the received transmission based on the indicated one or more first reference signal configurations. For example, one or more second reference signal configurations (e.g., to be used for a subsequent transmission) may be selected from a plurality of reference signal configurations based on the channel estimation measurement. For example, an indication of the selected one or more second reference signal configuration may be transmitted (e.g., to the base station).

Abstract: A reconfigurable intelligent surface (RIS) may include a multi-directional and fully connected load impedance network may be provided. The RIS may include a plurality of elements that are each configured to receive and/or transmit signals. Each element of the RIS may be connected to each of the other elements of the RIS via a multi-directional and fully connected load impedance network. The RIS may receive feedback that comprises channel quality information for a channel between the RIS and another device. The RIS may determine routing information for the RIS based on the feedback. The routing information may comprise a mapping of ingress signals to egress signals. A first signal may be received via an ingress element. The RIS may route and phase shift the first signal to an egress element based on the determined routing information. The RIS may transmit the phase shifted first signal via the second element.

Abstract: Methods and apparatuses for controlling a reconfigurable intelligent surface (RIS) to generate one or more modulated symbols may be described herein. The processor may be configured to generate an amplitude of the modulated symbol(s) by activating one or more of the plurality of portions of the RIS. The processor may be configured to generate a phase of modulated symbol(s) by controlling one or more phase shifts applied by one or more activated portions of the RIS. The method may include transmitting the one or more modulated symbols using the RIS. The method may include a RIS-based joint beamforming and/or modulation scheme with low PAPR. The RIS may be divided into one or more portions for attaining various gains. The RIS may be divided into an In-phase and/or Quadrature branches. The method may include an Amplitude-phase shift keying (A-PSK) and/or Quadrature amplitude-phase shift keying (AQ-PSK) joint beamforming and/or modulation scheme(s).

Abstract: Method, apparatus and systems are disclosed that may be implemented. One method implemented by a transceiver, is directed to transmission via a plurality of beams. The method includes obtaining an input bit stream and bit mapping bits of the input bit stream into at least a first stream and a second stream. The method further includes, generating one or more complex symbols using the first stream, selecting a Space-Time (ST) spreading matrix from a plurality of ST spreading matrices and spreading the generated one or more complex symbols over the selected ST spreading matrix to generate one or more dispersed ST codewords. In this method the transceiver maps the one or more dispersed ST codewords to a plurality of beams and transmits the mapped one or more dispersed ST codewords over the plurality of beams.