Telefonaktiebolaget Lm Ericsson (publ)

Roy Timo

Niklas Wernersson

Andreas Nilsson

Sven Oscar Petersson

Fredrik Athley

Xinlin Zhang

Maksym Girnyk

Zhao Wang

Sebastian Faxér

Simon Järmyr

Miguel Berg

Henrik Rydén

Hamed Farhadi

Sebastian FAXÉR

A method performed by a wireless device () for reporting channel state information (CSI) for a downlink channel is disclosed. The method comprises transmitting () a CSI report for the downlink channel to a network node (), the CSI report comprising: a set of reported coefficients; an indication of how the network node is to interpret the set of reported coefficients; and an indication of a payload size of the set of the reported coefficients.

Reporting of coefficients for channel state information

The present disclosure relates to a method performed by a wireless node () for transmitting reference symbols, the node comprising an antenna with a plurality of antenna ports, the method comprising configuring channel state information, CSI, measurements of a user equipment, UE (), by transmitting a downlink message, transmitting a first reference symbol using the plurality of antenna ports, wherein the first reference symbol is transmitted using a first number N of antenna ports, transmitting a second reference symbol using the plurality of antenna ports, wherein the second reference symbol is transmitted using a second number K of antenna ports, wherein the first reference symbol is transmitted using a first port distance smaller than a second port distance used when transmitting the second reference symbol, and wherein the K used antenna ports are less than the N used antenna ports.

Scalable method for obtaining UE-specific CSI

There is provided mechanisms for interference handling. A method is performed by a radio access network node. The method comprises obtaining an indication of interference in a time/frequency interval. The method comprises querying a neighbouring radio access network node about scheduling in the time/frequency interval of uplink wireless transmission from any terminal device served by the neighbouring radio access network node. The method comprises receiving a response from the neighbouring radio access network node. The response comprises information identifying uplink reference signal resources/ports, and their scheduling, as to be used by the terminal device scheduled in the time/frequency interval.

Interference handling at radio access network nodes

Embodiments include methods for operating a network node in a wireless network. Such embodiments include applying non-linear precoding to a first data stream to remove a representation of expected inter-stream interference due to a second data stream, thereby generating a corrected first data stream. Such embodiments also include applying linear precoding to the corrected first data stream and to a first reference signal (RS) stream to generate a first signal layer. The first RS stream is not corrected for the expected inter-stream interference prior to applying the linear precoding. Such embodiments also include transmitting the first signal layer to a user equipment (UE). Other embodiments include complementary methods performed by a UE, as well as network nodes and UEs configured to perform operations corresponding to such methods.

Methods for reference signal mapping in non-linear precoding MIMO transmission

There is provided mechanisms for transmission of reference signals. A method is performed by a terminal device. The terminal device comprises at least two physical antenna ports. The method comprises creating a virtual antenna port for, and applied over, at least two of the physical antenna ports. The method comprises transmitting, in the virtual antenna port, as many uplink reference signals as there are physical antenna ports.

Transmission of reference signals from a terminal device

In a first method, a wireless device estimates a delay profile of a channel impulse response, CIR, for a channel between a network node and the wireless device, compresses the delay profile using a compression function, and transmits the compressed delay profile. The compression function includes a first function and a quantizer. The first function is configured to receive input data and reduce a dimension of the input data. In a second method, a network node receives a compressed delay profile of CIR for a channel between a network node and a wireless device, decompresses the compressed delay profile using a decompression function, and estimates a position of the wireless device based on at least the decompressed delay profile. The decompression function includes a first function which is configured to receive input data and provide output data in a higher dimensional space than the input data.

Compression and decompression of delay profile

There is provided mechanisms for transmission of reference signals. A method is performed by a terminal device. The terminal device comprises at least two physical antenna ports. The method comprises obtaining channel information. The method comprises determining, for at least one given precoder in a codebook, an uplink reference signal to physical antenna port mapping based on the channel information. The method comprises transmitting uplink reference signals in the physical antenna ports according to the determined mapping.

A method performed by a radio unit for handling a number of received radio signals over an array of antennas comprised in the radio unit. The radio unit transforms the number of received radio signals into a number of sequences of complex symbols. The radio unit further filters the number of sequences of complex symbols by inputting the number of sequences of complex symbols into a trained computational model comprising an alternating sequence of linear and nonlinear functions and thereby obtaining a reduced number of sequences. The radio unit further transmits the reduced number of sequences to a baseband unit over a front-haul link.

Signal dimension reduction using a non-linear transformation

A network node determines parameters indicating a compression function for compressing downlink channel estimates, and a decompression function. The network node transmits the parameters, receives compressed downlink channel estimates, and decompresses the compressed downlink channel estimates using the decompression function. A terminal device receives the parameters, forms the compression function, compresses downlink channel estimates using the compression function, and transmits the compressed downlink channel estimates. The compression function comprises a first function formed based on at least some of the parameters, a second function which is non-linear, and a quantizer. The first function is configured to receive input data, and to reduce a dimension of the input data. The decompression function comprises a first function configured to receive input data and provide output data in a higher dimensional space than the input data, and a second function which is non-linear.

Compression and decompression of downlink channel estimates

A network node () determines parameters () indicating a compression function for compressing downlink channel estimates, and a decompression function. The network node transmits the parameters, receives compressed downlink channel estimates (), and decompresses the compressed downlink channel estimates using the decompression function. A terminal device () receives the parameters, forms the compression function, compresses downlink channel estimates using the compression function, and transmits the compressed downlink channel estimates. The compression function comprises a first function formed based on at least some of the parameters, a second function which is non-linear, and a quantizer. The first function is configured to receive input data, and to reduce a dimension of the input data. The decompression function comprises a first function configured to receive input data and provide output data in a higher dimensional space than the input data, and a second function which is non-linear.

There is provided mechanisms for transmission of reference signals. A method is performed by a terminal device. The terminal device is configured for codebook based precoding. The terminal device comprises at least two physical antenna ports. The method comprises transmitting, in all physical antenna port, as many uplink reference signals as there are physical antenna ports in total.

Growing community of inventors

Järfälla, Sweden

Roy Timo