Certain aspects of the present disclosure provide techniques for channel state information measurement adaptation to maximum multiple-input multiple-output layers. A method that may be performed by a user equipment (UE) includes receiving a first channel state information (CSI) report configuration including one or more first CSI reference signal (CSI-RS) resources, wherein each first CSI-RS resource comprises a first resource set; determining, based on an indication of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive, a first resource subset on which to report first CSI; and reporting the first CSI to a base station (BS), wherein the first CSI is based on the determined first resource subset.

There is provided mechanisms for controlling transmission from an antenna panel. The method is performed by a network apparatus. A method comprises performing time-domain beamformed communication with terminal devices served by the network apparatus using the antenna panel split into N>1 subpanels. Each subpanel has two input ports and is fed, via the input ports, by signals and configured to generate beams by application of antenna element weights to its antenna elements. The subpanels are at least phase-wise synchronized with each other. When one and the same signal is fed into the input ports of all the subpanels, signals as transmitted from the subpanels add up coherently to represent a 1-layer transmission by a time reference being shared between the subpanels. The time-domain beamformed communication is performed by the network apparatus using from 1 to 2N layers per symbol of a transmission time interval according to a mapping between the input ports and the signals as transmitted from the subpanels.

There is provided mechanisms for controlling transmission from an antenna panel. The method is performed by a network apparatus. A method comprises performing time-domain beamformed communication with terminal devices served by the network apparatus using the antenna panel split into N>1 subpanels. Each subpanel has two input ports and is fed, via the input ports, by signals and configured to generate beams by application of antenna element weights to its antenna elements. The subpanels are at least phase-wise synchronized with each other. When one and the same signal is fed into the input ports of all the subpanels, signals as transmitted from the subpanels add up coherently to represent a 1-layer transmission by a time reference being shared between the subpanels. The time-domain beamformed communication is performed by the network apparatus using from 1 to 2N layers per symbol of a transmission time interval according to a mapping between the input ports and the signals as transmitted from the subpanels.

An antenna system mounted on a vehicle according to the present invention may comprise: a first circuit board configured to be mountable to a metal frame; a second circuit board disposed so as to be spaced apart a predetermined distance from the first circuit board through a metal supporter; and an antenna configured to emit a signal transmitted from a power supply unit, said signal being transmitted through a space between the first circuit board and the second circuit board.

Provided is an antenna system mounted on a vehicle according to the present invention. The antenna system comprises: a first printed circuit board (PCB) having a metal pattern and a dielectric region; a second PCB on which a plurality of antennas are disposed; and a slot antenna configured to radiate a signal through a slot region formed adjacent to a junction portion of the first PCB and the second PCB.

The present disclosure provides a method (100) in a network device for channel estimation. The method (100) includes: transmitting (110) to a terminal device an instruction to precode each of a number, L, of DeModulation Reference Signals, DMRSs, using a number, N, of linearly independent precoders, respectively; receiving (120) from the terminal device L*N precoded DMRSs; estimating (130) an equivalent channel associated with an uplink channel from the terminal device to the network device based on one or more of the L*N precoded DMRSs; and determining (140) the uplink channel from the equivalent channel based on the N precoders.

A wireless communication network such as a 5G communication network can use MIMO technologies to enhance bandwidth between a wireless communications base station and one or more user equipment devices within a service area of the base station. RF signal repeaters can be utilized to provide one or more additional physical channels for communication between the MIMO base station and the MIMO user equipment. These RF signal repeaters can be regarded as increasing the MIMO channel diversity within the ambient environment.

A wireless communication network such as a 5G communication network can use MIMO technologies to enhance bandwidth between a wireless communications base station and one or more user equipment devices within a service area of the base station. RF signal repeaters can be utilized to provide one or more additional physical channels for communication between the MIMO base station and the MIMO user equipment. These RF signal repeaters can be regarded as increasing the MIMO channel diversity within the ambient environment.

In a multiuser (MU) multiple antenna system (MAS), a central processing unit is communicatively coupled to multiple distributed wireless terminals (WTs) via a network. The central processing unit processes channel measurements indicative of channel conditions between the multiple distributed WTs and a plurality of user devices and selects a plurality of WTs from the multiple distributed WTs to enhance channel space diversity within the MU-MAS. The central processing unit calculates (Multiple Input, Multiple Output) MIMO weights from the channel measurements for precoding a plurality of data streams that are transmitted concurrently from the plurality of WTs to the plurality of users, wherein the MIMO weights provide for a plurality of independent MIMO channels.

Based on the receipt of a demodulation reference signal from a user equipment, a determination can be made by the network node that a demodulation reference signal configuration is not suitable for the condition of a transmission link between the network node and the user equipment. In response to this determination, the demodulation reference signal configuration can be modified.