Abstract: A method for learning QoS performance inter-dependence of a plurality of communication links in a network managed by a central node, wherein the plurality of wireless links interface with a common application applying a joint figure of merit, comprising: selecting at least two links among the plurality of communication links; generating training requests respectively for each selected link; measuring QoS performance on each selected link for the training requests; and combining the measured QoS performance of the selected links, so as to obtain the QoS performance inter-dependence between the selected links.

Abstract: A method evaluates channel information of a database, DB, the DB channel information being associated to a target area and being representative of expected characteristics of a wireless communication channel in the target area to be provided to one or more communication devices. The method includes: obtaining, by a processing circuit, all or part of the DB channel information from the database; obtaining, by the processing circuit, observed channel information representative of characteristics of the wireless communication channel experienced by a first communication device in the target area; computing, by the processing circuit, a reliability indicator for the DB channel information for the target area, by comparing the DB channel information and the observed channel information and determining a timing information for the reliability indicator.

Abstract: A value of a first figure of merit representative of routing performance throughout the multi-hop network is obtained. Independently of the values of the first figure of merit, a value of a second figure of merit representative of transmission performance between the base station and the multi-hop network for each candidate configuration of transmission between the base station and the entry points of the multi-hop network is computed. Values of a third figure of merit representative of a trade-off between routing performance throughout the multi-hop network and transmission performance between the base station and the multi-hop network is then computed by combining values of the first figure of merit and of the second figure of merit. Then, the candidate configuration which shows the best value of the third figure of merit is selected to perform the transmission of data.

Abstract: The invention relates to a method of massive MIMO communication, comprising: —forming transmission beam set (?), by a base station (BS), with privileged channel directions; —designing additional beam set (?) for optimizing the transmission beam set, so as to detect channel direction change outside the privileged channel directions.

Abstract: The invention comprising: jointly determining an analog precoding matrix FRF and a plurality of multi-user groups Gl, each multi-user group Gl being associated to a respective subcarrier l, each multi-user group Gl containing a plurality of receivers to be jointly served for a data transmission on the respective subcarrier l; and using the analog precoding matrix FRF for processing at least one signal to transmit; characterized in that the joint determination comprises: /a/ optimizing a beamforming function ƒ(FRF, G1 . . . , GL) with respect to the analog precoding matrix FRF, the multi-user groups Gl being fixed; /b/ optimizing a scheduling function g(Gl,FRF) with respect to the multi-user groups Gl, a value of the analog precoding matrix FRF being fixed; wherein /a/ and /b/ are iteratively repeated.

Abstract: The invention comprising: jointly determining an analog precoding matrix FRF and a plurality of multi-user groups Gl, each multi-user group Gl being associated to a respective subcarrier l, each multi-user group Gl containing a plurality of receivers to be jointly served for a data transmission on the respective subcarrier l; and using the analog precoding matrix FRF for processing at least one signal to transmit; characterized in that the joint determination comprises: /a/ optimizing a beamforming function ƒ(FRF, G1 . . . , GL) with respect to the analog precoding matrix FRF, the multi-user groups Gl being fixed; /b/ optimizing a scheduling function g(Gl,FRF) with respect to the multi-user groups Gl, a value of the analog precoding matrix FRF being fixed; wherein /a/ and /b/ are iteratively repeated.

Abstract: A method for enabling hybrid beamforming in a communication system including a transmitter being able to serve a plurality of receivers, wherein a frequency band comprises at least one subcarrier, wherein each receiver is associated to a set Cprec,k of analog precoding codewords, said method comprising: —for each receiver, computing (202) an analog precoding matrix FRF k associated to said receiver; said computation (202) comprising: /a/ for each subcarrier, performing (202a) a Singular Value Decomposition, SVD, on a channel matrix associated to said receiver and to said each subcarrier; /b/ for each subcarrier, determining a first decomposition matrix Vk(1) based on the relative SVD; /c/ determining (303) an analog precoding codeword which optimizes a first function g1(Vk(1), . . . , Vk(L), F) of Vk(1), . . . , Vk(L) and F, for a plurality of F E Cprec,k, wherein L denotes a number of subcarriers.

Abstract: The present invention relates to a method of channel estimation including: —reception of measurements from a transmitter having a plurality of transmit antennas at a receiver having a plurality of receive antennas; characterized in that the method includes: —a first determination of at least one set of angles of departure based on the received measurements, each angle of departure being associated to at least one path of the channel for a radio transmission between the transmitter and the receiver; —a second determination of a plurality of sets of at least one parameter based on the determined set of angles of departure, each set of at least one parameter being associated to a path of the channel for a radio transmission between the transmitter and the receiver.

Abstract: For determining, in a distributed fashion, precoders to be applied for performing transmissions of data between a plurality of transmitters and a plurality of receivers via a global MIMO channel H of a wireless communication system, said precoders jointly forming an overall precoder V, each and every j-th transmitter perform: gathering long-term statistics of CSIT errors incurred by each one of the transmitters; obtaining short-term CSIT related data and building therefrom its own view ?(j) of the global MIMO channel H; determining an estimate {tilde over (V)}(j) of the overall precoder V from the short-term CSIT related data; refining the estimate {tilde over (V)}(j) on the basis of the gathered long-term statistics of CSIT errors so as to obtain a refined precoder {tilde over (V)}(j) that is a view of the overall precoder V from the standpoint of said j-th transmitter, further on the basis of its own view ?(j) of the global MIMO channel H, and further on the basis of a figure of merit representative of perf

Abstract: A method for enabling hybrid beamforming in a communication system including a transmitter being able to serve a plurality of receivers, wherein a frequency band comprises at least one subcarrier, wherein each receiver is associated to a set Cprec,k of analog precoiling codewords, said method comprising: —for each receiver, computing (202) an analog precoding matrix FRF k associated to said receiver; said computation (202) comprising: /a/ for each subcarrier, performing (202a) a Singular Value Decomposition, SVD, on a channel matrix associated to said receiver and to said each subcarrier; /b/ for each subcarrier, determining a first decomposition matrix Vk(1) based on the relative SVD; /c/ determining (303) an analog precoding codeword which optimizes a first function g1(Vk(1), . . . , Vk(L), F) of Vk(1), . . . , Vk(L) and F, for a plurality of F E Cprec,k, wherein L denotes a number of subcarriers.

Abstract: For determining parameters for configuring a regularized zero-forcing precoder aiming at being applied for transmitting data from a plurality of transmitters to a plurality of receivers via a MIMO transmission channel in a wireless communication system, and more particularly in a scope of massive MIMO approach, a first phase comprises: obtaining long-term statistics about observations of the MIMO transmission channel, and obtaining a power scaling factors aiming at meeting a power constraint P, by solving an optimization problem as a function of a signal to noise ratio asymptotic expression from the standpoint of each receiver. Then, a second phase comprises: obtaining an estimation of the MIMO transmission channel, and configuring the regularized zero-forcing precoder using the power scaling factors determined in the first phase as well as the obtained estimation of the MIMO transmission channel.

Abstract: For setting cooperation parameters of a communication system including a plurality of node devices interconnected by links and adapted to be respectively configured according to said cooperation parameters, a cooperation phase comprises: gathering measurements data representative of measurements of the random variables; optimizing the figure of merit for determining said cooperation parameters, on the basis of the obtained measurements. At least one link implying quantization operations relying on a codebook for gathering said measurements data and/or for providing said cooperation parameters, a pre-processing phase comprises beforehand: obtaining statistics data relative to a probability distribution of said random variables; and determining every codebook on the basis of the figure of merit, such that the figure of merit is statistically optimized according to the obtained statistics.

Abstract: For determining parameters for configuring a regularized zero-forcing precoder aiming at being applied for transmitting data from a plurality of transmitters to a plurality of receivers via a MIMO transmission channel in a wireless communication system, and more particularly in a scope of massive MIMO approach, a first phase comprises: obtaining long-term statistics about observations of the MIMO transmission channel, and obtaining a power scaling factors aiming at meeting a power constraint P, by solving an optimization problem as a function of a signal to noise ratio asymptotic expression from the standpoint of each receiver. Then, a second phase comprises: obtaining an estimation of the MIMO transmission channel, and configuring the regularized zero-forcing precoder using the power scaling factors determined in the first phase as well as the obtained estimation of the MIMO trans mission channel.

Abstract: For setting cooperation parameters of a communication system including a plurality of node devices interconnected by links and adapted to be respectively configured according to said cooperation parameters, a cooperation phase comprises: gathering measurements data representative of measurements of the random variables; optimizing the figure of merit for determining said cooperation parameters, on the basis of the obtained measurements. At least one link implying quantization operations relying on a codebook for gathering said measurements data and/or for providing said cooperation parameters, a pre-processing phase comprises beforehand: obtaining statistics data relative to a probability distribution of said random variables; and determining every codebook on the basis of the figure of merit, such that the figure of merit is statistically optimized according to the obtained statistics.