Abstract: Embodiments of the invention provides a decoder for decoding a signal received through a transmission channel in a communication system, said signal carrying information symbols selected from a given alphabet and being associated with a signal vector, said transmission channel being represented by a channel matrix, wherein said decoder comprises: a sub-block division unit (301) configured to divide the received signal vector into a set of sub-vectors in correspondence with a division of a matrix related to said channel matrix; a candidate set estimation unit (305) for recursively determining candidate estimates of sub-blocks of the transmitted signal corresponding to said sub-vectors, each estimate of a given sub-block being determined from at least one candidate estimate of the previously processed sub-blocks, wherein said candidate set estimation unit is configured to determine a set of candidate estimates for at least one sub-block of the transmitted signal by applying at least one iteration of a decodi

Abstract: A method, device, and a computer program are provided to decode a signal received through a transmission channel in a communication system, the received signal being represented by a signal vector.

Abstract: There is provided a decoder for decoding a data signal received through a transmission channel in a communication system, the decoder (310) comprising a symbol estimation unit (311) configured to determine estimated symbols representative of the transmitted symbols carried by the received signal, the estimated symbols being determined from nodes of a decoding tree based on a weight metric associated with each of the node. The decoder further comprises a termination alarm monitoring unit (312) for monitoring a termination alarm depending on the current decoding computation complexity, the termination alarm being associated with a metric parameter, the symbol estimation unit being configured to reduce the weight metric of each node of the decoding tree by a quantity corresponding to a function of the metric parameter associated with the termination alarm, in response to the triggering of the termination alarm.

Abstract: Embodiments of the invention provide a decoder for decoding a signal received through a transmission channel in a communication system, said signal comprising a vector of information symbols, said transmission channel being represented by an upper triangular matrix, wherein the decoder comprises: a processing unit (309) configured to determine a set of division parameters depending on at least one division metric derived from components of said upper triangular matrix; a decoding unit (311) configured to divide said upper triangular matrix into two or more sub-matrices using said set of division parameters in accordance with a division of said vector of information symbols into two or more sub-vectors, and to determine at least one estimate of each sub-vector of information symbols by applying a symbol estimation algorithm, wherein the decoder is configured to determine at least one estimate of said vector of information symbols from the estimates of said sub-vectors of information symbols.

Abstract: Embodiments of the invention provide a decoder for decoding a signal received through a transmission channel in a communication system, said signal comprising a vector of information symbols, wherein the decoder comprises: a processing unit (307) configured to determine at least one candidate set of division parameters and to perform a division of said vector of information symbols into a set of sub-vectors in association with each candidate set of division parameters, each pair of sub-vectors being associated with a division metric; a selection unit (309) configured to select one of said candidate sets of division parameters according to a selection criterion depending on said division metric; and a decoding unit (311) configured to determine at least one estimate of each sub-vector associated with said selected set of division parameters by applying a symbol estimation algorithm, wherein the decoder is configured to determine at least one estimate of the vector of information symbols from said at least

Abstract: There is provided a decoder (310) for sequentially decoding a data signal received through a transmission channel in a communication system, the received data signal carrying transmitted symbols, the decoder comprising a symbol estimation unit (311) configured to determine estimated symbols representative of the transmitted symbols carried by the received signal from information stored in a stack, the stack being filled by iteratively expanding child nodes of a selected node of a decoding tree comprising a plurality of nodes, each node of the decoding tree corresponding to a candidate component of a symbol of the received data signal and each node being associated with a predetermined metric, the stack being filled at each iteration with at least some of the expanded child nodes and being ordered by increasing values of the metrics associated with the nodes, the selected node for each iteration corresponding to the node having the lowest metric in the stack.

Abstract: Embodiments of the invention provide a decoder for decoding a data signal received through a transmission channel in a communication system, said transmission channel being represented by an upper triangular matrix, said signal carrying transmitted symbols, each symbol carrying a set of information bits, wherein said decoder comprises: a processing unit (213) configured to determine at least one sub-block decoding parameter given a target quality of service metric; A sub-block decoding unit (214) configured to divide said data signal into a number of sub-vectors based on said at least one sub-block decoding parameter in accordance with a division of said upper triangular matrix into a number of sub-matrices, said sub-block decoding unit (214) being further configured to determine at least one estimate of each sub-vector of transmitted symbols from said sub-vectors, and determine an estimate of the transmitted symbols from said estimates.

Abstract: There is provided a method of generating a space-time block code (STBC) for encoding a digital data sequence comprising a set of independent symbols to be transmitted through a transmission channel in a communication system, the space-time block code being represented by a set of linear dispersion matrices in a linear dispersion representation, each linear dispersion matrix comprising components having complex values, the method comprising, generating at least some of the linear dispersion matrices depending on component-wise conditions related to a set of selected pairs of the linear dispersion matrices, each pair comprising a first linear dispersion matrix and a second linear dispersion matrix, said component-wise conditions comprising a component-wise condition between the components of the first linear dispersion matrix and the components of the second linear dispersion matrix.

Abstract: Embodiments of the invention provides a deterministic scrambler (1) arranged in a multimode optical fiber (130) for scrambling light, the light comprising a set of optical signals propagated in said multimode optical fiber according to a set of propagation modes, each propagation mode being associated with a power value, wherein the scrambler is configured to determine a permutation of said propagation modes depending on the power values associated with said propagation modes, the scrambler being configured to redistribute the optical signals according to said permutation of the propagation modes.

Abstract: Embodiments of the invention provide an optical transmitter configured to transmit a data sequence over at least two spatial propagation modes through an optical transmission channel in a multi-mode optical fiber transmission system, the transmission system being associated with a predefined value of a mode-dependent loss, wherein the optical transmitter comprises: a forward error correcting code encoder (22) configured to encode said data sequence into a codeword vector by applying at least one error correcting code; a modulator (23) configured to determine a set of modulated symbols by applying a modulation scheme to said codeword vector; and a Space-Time encoder (24) configured to determine a codeword matrix by applying a Space-Time code to said set of modulated symbols.

Abstract: Embodiments of the invention provide a Space-Time coding device for encoding a digital data sequence according to a predefined space-time coding rate, said data sequence comprising a set of modulated symbols to be transmitted over at least two propagation modes, during a number of time slots, through an optical transmission channel in a single-core multimode optical fiber transmission system, wherein the device comprises: a codebook generator (53) configured to determine a set of codeword matrices defining a space-time code represented by a space dimension and a temporal dimension, each codeword matrix comprising complex values and a number of columns equal to said code temporal dimension, and a number of rows equal to said code space dimension, the codebook generator (53) being further configured to associate a difference codeword matrix and a distance metric to each pair of codeword matrices among said set of codeword matrices, each component of a difference codeword matrix associated with a given pair o

Abstract: Embodiments of the invention provide a decoder for decoding a signal represented by a vector of information symbols received through a transmission channel in a communication system, said the transmission system being represented by a channel state matrix, said information symbols being selected from a given set of values carrying a set of information bits, wherein said decoder comprises: a division unit (202) configured to divide the channel state matrix into a number of sub-blocks of column vectors, in accordance with a division of said vector of information symbols into a number of sub-vectors; a permutation unit (203) configured to determine a set of permuted channel state matrices by permuting said sub-blocks of column vectors, the permutation unit (203) being further configured to select at least one permuted channel state matrix among said set of permuted channel state matrices according to a selection criterion; a sub-block decoding unit (207) configured to determine a transformed signal from said

Abstract: Embodiments of the invention provide a decoder for decoding a signal received through a transmission channel in a communication system, said signal comprising a vector of information symbols, said transmission channel being represented by a channel matrix comprising column vectors, said information symbols carrying information bits, wherein the decoder comprises: a transformation unit (401) configured to determine a set of auxiliary channel matrices, each auxiliary channel matrix being determined by performing a linear combination of at least one of the column vectors of said channel matrix; a decomposition unit (407) configured to determine a decomposition of each auxiliary channel matrix into an upper triangular matrix and an orthogonal matrix; a matrix selection unit (409) configured to select at least one auxiliary channel matrix among said set of auxiliary channel matrices depending on a selection criterion related to the components of said upper triangular matrices.

Abstract: Embodiments of the invention provide a decoder for decoding a signal received through a transmission channel in a communication system, said signal comprising a vector of information symbols, said transmission channel being represented by a channel matrix, wherein the decoder comprises: an initial radius determination unit (307) configured to determine an initial radius; a symbol estimation unit (309) configured to iteratively determine a current radius to search a lattice point inside a current spherical region defined by said current radius, said current radius being initially set to said initial radius, said symbol estimation unit (309) being configured, for each lattice point found in said current spherical region, to store said lattice point in association with a metric, said symbol estimation unit (309) being further configured to update said current radius using a linear function, said linear function having a slope parameter strictly inferior to one, The decoder being configured to determine at

Abstract: Methods, systems, and computer program products for decoding a received data signal in a communication system by iteratively constructing a decoding tree, each node of said decoding tree corresponding to a component of a symbol of said data signal, and being associated with a metric, the construction of the decoding tree implementing at least one iteration of the following steps, for a current node of the tree stored in the top of a stack: generating (102) a reference child node of said current node from said vector representing the received data signal, from the reference child node, generating (106) a first neighbor child node by subtracting a positive integer parameter from the value of the reference node, and a second neighbor child node by adding said positive integer parameter to the value of the reference child node; storing (108) in said stack three child nodes deriving from the reference child node and from said first and second neighbor child nodes, each child node being stored in the stack in as

Abstract: The invention relates to a mode selection method for a system for MIMO transmission on an optical fiber of multimode type. It comprises a step of measuring the transfer matrix of the transmission channel made up of a set of modes of the optical fiber (110), a step of transforming (120) the transfer matrix into a block diagonal matrix, each block being associated with a mode subset, a step of determining (130) the gain and/or the transmission capacity for each of the mode subsets, and a selection (140) of the mode subset corresponding to the highest gain and/or capacity, the MIMO transmission system then using only the modes of the subset thus selected to transmit on the optical fiber. The invention relates also to a core selection method for a system for MIMO transmission on optical fiber of multicore type.

Abstract: The invention relates to a system and a method for transmission over optical fiber (130) with mode or core scrambling. The system comprises a spatio-temporal encoder (110) and a plurality of modulators (1251, . . . , 125n) associated, respectively, with separate propagation modes or cores of said fiber, each modulator modulating a laser beam. Said fiber comprises a plurality of slices (1301, . . . , 130L), an amplifier (140l) being provided between any two consecutive slices of the optical fiber. A mode scrambler (150l) is associated with each amplifier in order to perform a permutation of said modes between at least two consecutive slices.

Abstract: Embodiments of the invention provide a decoder for decoding a data signal received through a transmission channel in a communication system, said transmission channel being represented by an upper triangular matrix, said signal carrying transmitted symbols, each symbol carrying a set of information bits, wherein said decoder comprises: a processing unit (213) configured to determine at least one sub-block decoding parameter given a target quality of service metric; A sub-block decoding unit (214) configured to divide said data signal into a number of sub-vectors based on said at least one sub-block decoding parameter in accordance with a division of said upper triangular matrix into a number of sub-matrices, said sub-block decoding unit (214) being further configured to determine at least one estimate of each sub-vector of transmitted symbols from said sub-vectors, and determine an estimate of the transmitted symbols from said estimates.

Abstract: Embodiments of the invention provide a decoder for decoding a signal represented by a vector of information symbols received through a transmission channel in a communication system, said the transmission system being represented by a channel state matrix, said information symbols being selected from a given set of values carrying a set of information bits, wherein said decoder comprises: a division unit (202) configured to divide the channel state matrix into a number of sub-blocks of column vectors, in accordance with a division of said vector of information symbols into a number of sub-vectors; a permutation unit (203) configured to determine a set of permuted channel state matrices by permuting said sub-blocks of column vectors, the permutation unit (203) being further configured to select at least one permuted channel state matrix among said set of permuted channel state matrices according to a selection criterion; a sub-block decoding unit (207) configured to determine a transformed signal from said

Abstract: Embodiments of the invention provide a decoder (10) for decoding a signal received through a transmission channel in a communication system, the signal carrying information symbols selected from a given set of values and being associated with a signal vector, the transmission channel being represented by a channel matrix. The decoder comprises : a sub-block division unit (12) configured to divide the received signal vector into a set of sub-vectors in correspondence with a division of a matrix related to said channel matrix ; at least one weighting coefficient calculation unit (14) configured to calculate a sub-block weighting coefficient for each sub-vector, at least one symbol estimation unit (11) for recursively determining estimated symbols representative of the transmitted symbols carried by the data signal from information stored in a stack.