Abstract: In accordance with an example embodiment of the present invention, a method comprising: receiving, by a user equipment of a communication network, a request from a network node to use at least two beam configurations of multiple different beam configurations for the user equipment; measuring, by the user equipment, downlink received power on at least one reference signal using the at least two beam configurations; sending, by the user equipment on an uplink, information of at least two downlink received powers and at least one reference signal using the at least two beam configurations; receiving, by the user equipment, signaling from the network node comprising an indication of beam correspondence assessment from the network node; and adjusting, by the user equipment, uplink beam with reference to a downlink beam based on the received indication of beam correspondence assessment.

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: In accordance with an example embodiment of the present invention, a method comprising: receiving, by a user equipment of a communication network, a request from a network node to use at least two beam configurations of multiple different beam configurations for the user equipment; measuring, by the user equipment, downlink received power on at least one reference signal using the at least two beam configurations; sending, by the user equipment on an uplink, information of at least two downlink received powers and at least one reference signal using the at least two beam configurations; receiving, by the user equipment, signaling from the network node comprising an indication of beam correspondence assessment from the network node; and adjusting, by the user equipment, uplink beam with reference to a downlink beam based on the received indication of beam correspondence assessment.

Abstract: An UL channel for a UE is measured based on reference signal (s) to determine UL channel information. DL channel information is inferred based on UL-DL channel reciprocity and the determined UL channel information. Reporting is configured based on the inferred DL channel information for CSI for the UE and resource (s) are allocated for the UE to use to report the CSI. Information is signaled to the UE indicating a configuration of the reporting of CSI and the resource (s). DL reference signal (s) are transmitted toward the UE to be used for determination of the CSI. Report (s) of CSI are received on the allocated resource (s). The UE receives the configuration, determines the CSI using the configuration and the received DL reference signal (s) and fits the determined CSI into the allocated resource (s). The UE transmits the determined CSI on the allocated resource (s).

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: 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: 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: 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.