Abstract: There is provided a method at a network node of a communication network, comprising: receiving an uplink reference signal from a user equipment; estimating, based on the received uplink reference signal, delay information regarding a delay profile of a communication channel between the user equipment and the network node and spatial information regarding the communication channel; applying both the delay information and the spatial information in precoding of at least one downlink reference signal; transmitting the at least one precoded downlink reference signal to the user equipment; and receiving, from the user equipment as a response to the transmission of the at least one precoded downlink reference signal, channel information, the channel information indicating at least non-zero coefficients of at least one channel transmission layer.

Abstract: A method, apparatus, and a computer-readable storage medium are provided for partial reciprocity-based adaptive port selection codebook configuration. A method, apparatus, and a computer-readable storage medium are provided for partial reciprocity- based adaptive port selection codebook configuration. In an example implementation, the method may include a user equipment receiving at least one channel state information reporting configuration from a network node, the at least one channel state information reporting configuration including precoding matrix indicator as reporting quantity and an adaptive port selection codebook configuration for the precoding matrix indicator and determining whether partial reciprocity operations for adaptive port selection precoding matrix indicator are activated, the determining based at least on information in a sounding reference signal (SRS) request field of a downlink control information, an active semi- persistent SRS, or a periodic SRS configured by higher layers.

Abstract: Systems, methods, apparatuses, and computer program products for co-polarized transmission and port selection associated therewith are provided. For example, a method can include feeding back compressed channel state information. The channel state information can include combining coefficients used to combine a number of space domain, frequency domain, or both space and frequency domain ports. At least one layer can be restricted to be transmitted on one polarization. The feedback for the at least one layer only involves the combining coefficients on the one polarization.

Abstract: A technique includes receiving an uplink grant that indicates a size (M) of uplink resources allocated to the user device sub-band precoder indications; determining a set of uplink sub-band allocation parameters, including at least: a total number of bits (N) for sub-band precoder indications (where N remains constant for different values of M); a number of bits (m) per each of the sub-band precoder indications; and a sub-band size (J) for each of the one or more sub-bands; wherein at least one of the number of bits (m) per sub-band precoder indication and the sub-band size (J) for each of the one or more sub-bands changes or is a different value based on different sizes (M) of uplink resources; decoding each of the one or more sub-band precoder indications; and precoding, based on the one or more sub-band precoder indications, data for transmission via the one or more sub-bands.

Abstract: Systems, methods, apparatuses, and computer program products for non-linear precoding are provided. One method may include combining, by a network node, of linear and non-linear precoding, for example based on specific channel state information acquisition from at least one user equipment, and generating two types of demodulation reference signals for the concatenated linear and non-linear precoding. The method may include multiplexing, by the network node, the two types of demodulation reference signals with data. A first of the two types of demodulation reference signals may be linearly precoded with one linear precoding matrix from a first-stage linear precoder, and another one of the two types may be linearly precoded with both the first-stage linear precoder and a feedforward filter in a second-stage non-linear precoder from the concatenation of linear and nonlinear precoders.

Abstract: Systems, methods, apparatuses, and computer program products for non-linear precoding in radio access networks are provided. One method may include, when it is determined that a user equipment is capable of being non-linearly precoded, determining one of two non-linear precoding modes and indicating the determined non-linear precoding mode to the user equipment. One of the two non-linear precoding modes is configured to use explicit beamformed channel state information, and the other one of the two non-linear precoding modes is configured to use explicit full downlink channel state information.

Abstract: Systems, methods, apparatuses, and computer program products for dynamic and partial sharing of the channel measurement downlink (DL)-reference signal (RS) resources are provided.

Abstract: An example of an embodiment is a method including: allocating, by a network node, an uplink non-orthogonal reference signal sequence to each of a plurality of user equipments within a cooperation area; receiving, from at least one user equipment of the plurality of user equipments, the uplink non-orthogonal reference signal allocated to the at least one user equipment; and determining channel state information for the at least one user equipment based on the received uplink non-orthogonal reference signal.

Abstract: A method for implementing co-polarized feedback for frequency domain compression is disclosed. The method includes feeding back compressed channel state information, wherein at least one layer is restricted to be transmitted on one polarization and the feedback for the at least one layer only involves the channel state information on the one polarization.

Abstract: Various communication system may benefit from the appropriate selection of communication parameters. For example, certain wireless communication systems may benefit from the user of a low-overhead high-rank codebook. A method can include determining a first partition of a precoding matrix with a higher resolution and a second partition of the precoding matrix with a lower resolution. The method can also include feeding back the first partition and the second partition.

Abstract: Systems, methods, apparatuses, and computer program products for non-linear precoding in radio access networks are provided. One method may include, when it is determined that a user equipment is capable of being non-linearly precoded, determining one of two non-linear precoding modes and indicating the determined non-linear precoding mode to the user equipment. One of the two non-linear precoding modes is configured to use explicit beamformed channel state information, and the other one of the two non-linear precoding modes is configured to use explicit full downlink channel state information.

Abstract: Systems, methods, apparatuses, and computer program products for non-linear precoding are provided. One method may include combining, by a network node, of linear and non-linear precoding, for example based on specific channel state information acquisition from at least one user equipment, and generating two types of demodulation reference signals for the concatenated linear and non-linear precoding. The method may include multiplexing, by the network node, the two types of demodulation reference signals with data. A first of the two types of demodulation reference signals may be linearly precoded with one linear precoding matrix from a first-stage linear precoder, and another one of the two types may be linearly precoded with both the first-stage linear precoder and a feedforward filter in a second-stage non-linear precoder from the concatenation of linear and nonlinear precoders.

Abstract: A method for implementing co-polarized feedback for frequency domain compression is disclosed. The method includes feeding back compressed channel state information, wherein at least one layer is restricted to be transmitted on one polarization and the feedback for the at least one layer only involves the channel state information on the one polarization.

Abstract: In accordance with an example embodiment of the present invention, an apparatus comprising: at least one processor; and at least one memory including computer program code, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to perform at least the following: allocate a physical uplink channel between at least one integrated access and backhaul node user equipment function and a parent distributed unit; and send at least one message via the physical uplink channel, wherein the at least one message includes at least: a destination queue depth scheduled on a downlink by at least one integrated access and backhaul node distributed unit.

Abstract: A method and apparatus may include measuring a space frequency downlink channel matrix. The space frequency downlink channel matrix reflects a channel response observed by the apparatus. The apparatus receives transmissions from an array of antennas of a network node. The method can also include determining a spatial channel vector. The method can also include determining scalar phase terms. The method can also include determining a Signal-to-Interference-Plus-Noise-Ratio scalar factor of the channel response observed by the apparatus. The method can also include transmitting an encoded form of the spatial channel vector. The method can also include transmitting an encoded form of the Signal-to-Interference-Plus-Noise-Ratio scalar factor. The method can also include transmitting an encoded form of the scalar phase terms.

Abstract: Various communication systems may benefit from improved sounding reference symbol sounding techniques. An apparatus may comprise at least one memory comprising computer program code and at least one processor. The at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus at least to precode at least one uplink sounding reference symbol based upon at least one initial rank indicator and at least one first vector/matrix received from a network entity. The apparatus further transforms the first vector/matrix and a second vector matrix received from the network entity into a third vector/matrix based upon a final rank indicator received from the network entity. The apparatus further transmits data based upon the third vector/matrix.

Abstract: A technique of reducing interference at a wireless node includes: determining a location of a base station relative to a wireless node, determining, based at least on the location of the base station relative to the wireless node, a beam-reduction region that includes one or more interfering transmit beams of the base station within the beam-reduction region, and causing the base station to decrease a transmit power for the one or more interfering transmit beams within the beam-reduction region.

Abstract: A technique includes receiving an uplink grant that indicates a size (M) of uplink resources allocated to the user device sub-band precoder indications; determining a set of uplink sub-band allocation parameters, including at least: a total number of bits (N) for sub-band precoder indications (where N remains constant for different values of M); a number of bits (m) per each of the sub-band precoder indications; and a sub-band size (J) for each of the one or more sub-bands; wherein at least one of the number of bits (m) per sub-band precoder indication and the sub-band size (J) for each of the one or more sub-bands changes or is a different value based on different sizes (M) of uplink resources; decoding each of the one or more sub-band precoder indications; and precoding, based on the one or more sub-band precoder indications, data for transmission via the one or more sub-bands.

Abstract: Various communication system may benefit from the appropriate selection of communication parameters. For example, certain wireless communication systems may benefit from the user of a low-overhead high-rank codebook. A method can include determining a first partition of a precoding matrix with a higher resolution and a second partition of the precoding matrix with a lower resolution. The method can also include feeding back the first partition and the second partition.

Abstract: Various communication systems may benefit from improved sounding reference symbol sounding techniques. An apparatus may comprise at least one memory comprising computer program code and at least one processor. The at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus at least to precode at least one uplink sounding reference symbol based upon at least one initial rank indicator and at least one first vector/matrix received from a network entity. The apparatus further transforms the first vector/matrix and a second vector matrix received from the network entity into a third vector/matrix based upon a final rank indicator received from the network entity. The apparatus further transmits data based upon the third vector/matrix.