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: 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 includes determining a number of polarizations. The method also includes determining a number of receive antennas that have a same polarization, determining a total number of receive antennas based on the number of polarizations and the number of receive antennas that have the same polarization; and applying singular value decomposition precoding on all the receive antennas with the same polarization.

Abstract: Systems, methods, apparatuses, and computer program products for determining transmit weights are provided. One method includes selecting users to pair for multi-user multiple input multiple output transmission, calculating multi-user multiple input multiple output (MU-MIMO) transmit weights in a communication system employing an analog electrically steered array with Q antennas, applying the multi-user multiple input multiple output weights to the transmitted signals, and transmitting the weighted signals from an antenna array. The calculating may include calculating the MU-MIMO transmit weights so that a sum of power across a same element of the selected users' weight vectors is equal on all of the antennas and one of either sum throughput across users or sum signal to interference plus noise ratio (SINR) across users is maximized.

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: Systems, methods, apparatuses, and computer program products relating to support MIMO on the UL with flexibility and enhanced performance, for example, in 5G or new radio access technology (NR).

Abstract: Systems, methods, apparatuses, and computer program products for a UE-specific codebook design are provided. One method may include determining, by a network node, variable spacing between antenna elements of a user equipment. The method may also include configuring user equipment specific precoders based on the variable spacing between the user equipment antenna elements.

Abstract: A method and apparatus may include receiving, by a first network node, mapping information from at least one second network node. The mapping information indicates restrictions with respect to antenna ports to be used for measurements on each of one or more channel-state-information-reference-signal resources transmitted by at least one second network node. The method may also include transmitting a message to a user equipment. The message configures the user equipment to measure channel-state-information-reference-signal-received power from at least one of said one or more channel-state-information-reference-signal resources. The method may also include receiving a reporting from the user equipment.

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: Systems, methods, apparatuses, and computer program products relating to support MIMO on the UL with flexibility and enhanced performance, for example, in 5G or new radio access technology (NR).

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 determining transmit weights are provided. One method includes selecting users to pair for multi-user multiple input multiple output transmission, calculating multi-user multiple input multiple output (MU-MIMO) transmit weights in a communication system employing an analog electrically steered array with Q antennas, applying the multi-user multiple input multiple output weights to the transmitted signals, and transmitting the weighted signals from an antenna array. The calculating may include calculating the MU-MIMO transmit weights so that a sum of power across a same element of the selected users' weight vectors is equal on all of the antennas and one of either sum throughput across users or sum signal to interference plus noise ratio (SINR) across users is maximized.

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: Various communication systems may benefit from managing signal interference. For example, certain wireless communication systems may benefit from a dynamic time division duplex system involving slot allocation. A method includes allocating, by an access point, in a time division duplex frame a plurality of radio resource slots, each one of the plurality of radio resource slots being allocated for a downlink or an uplink transmission, and determining that the allocation of the downlink or uplink transmission should be changed. The method also includes applying a permutation pattern to re-allocate at least one of the plurality of radio resource slots for the downlink or uplink transmission.

Abstract: A method and apparatus may include receiving, by a first network node, mapping information from at least one second network node. The mapping information indicates restrictions with respect to antenna ports to be used for measurements on each of one or more channel-state-information-reference-signal resources transmitted by at least one second network node. The method may also include transmitting a message to a user equipment. The message configures the user equipment to measure channel-state-information-reference-signal-received power from at least one of said one or more channel-state-information-reference-signal resources. The method may also include receiving a reporting from the user equipment.

Abstract: An example implementation may include transmitting, by a first base station to a second base station, a beam-specific power down request value for one or more beams. Another example implementation may include receiving, by a second base station from a first base station, a beam-specific power down request value for one or more beams, and decreasing, by the second base station, transmit power for one or more transmit beams based on the beam-specific power down request value for the one or more beams.

Abstract: Various communication systems may benefit from codebook methods and devices for multiple transmitters. For example, a codebook for four transmitters (4Tx) may provide further enhancement for downlink multiple-input multiple-output (DL-MIMO) systems. A method can include weighting a signal for transmission based on a precoder selected according to a feedback from a codebook, such as codebooks A, B, C, D, or E, described herein. The method can also include sending the weighted signal.

Abstract: Various communication systems may benefit from managing signal interference. For example, certain wireless communication systems may benefit from a dynamic time division duplex system involving slot allocation. A method includes allocating, by an access point, in a time division duplex frame a plurality of radio resource slots, each one of the plurality of radio resource slots being allocated for a downlink or an uplink transmission, and determining that the allocation of the downlink or uplink transmission should be changed. The method also includes applying a permutation pattern to re-allocate at least one of the plurality of radio resource slots for the downlink or uplink transmission.

Abstract: Systems and techniques for joint transmission cooperative multi-point. A set of n CSI reference signal resources are to be measured by a user device. The n CSI reference signal resources include at least one CSI reference signal resource spanning over at least two transmission points. Channel state information feedback corresponding to each CSI reference signal resource is configured. Upon receiving CSI from the user device, at least one precoder is selected for coherent joint cooperative multipoint transmission based on inter-transmission point phase relationship information. A co-phasing factor is derived from transmitted precoders over a cross-cell CSI reference signal resource, the derivation including transmission of reference signals using first and second precoding vectors on two ports, computation of a third vector using feedback based on the precoded reference signals, and computation of the co-phasing factor based on the first, second, and third vectors.

Abstract: Systems and techniques for elevation beam design. Characteristics, such as number, distribution, and geographical location of elements subject to interference by elevation beams of a base station are analyzed, and a configuration for an antenna array is determined so as to create a set of elevation beams directed so as to avoid interference with the elements subject to interference by the base station. Configuration may, for example, include configuration of the antenna array so as to create a set of elevation beams exhibiting nulls and sidelobes in appropriate locations and at appropriate angles so as to avoid interference.