B-com

Fondation B Com

Broadcom Corporation

Renesas Mobile Corporation

Stéphane Paquelet

Luc Le Magoarou

Patrick Savelli

Pascal Le Corre

Antoine Le Calvez

Remi Bonnefoi

Ali Zeineddine

Matthieu Roy

Rémi Bonnefoi

A method for detecting (DET) a signal in a communication system including a plurality of communication channels, from a plurality of noisy values respectively representative of the transmission through the communication channels, is provided. The propagation in the communication channels is characterized by at least one variable. The set of values that can be taken by the variable is divided into a plurality of ranges. The method includes receiving (E) the signals respectively transmitted in the plurality of communication channels, and detecting (E) a signal corresponding to a value of the variable lying within one of the plurality of ranges by comparing, with a predetermined threshold, a value taken by a correlator linked to the range in question and calculated as a function of the noisy values. A channel estimation method, a detection device, a channel estimation device and a computer program are also described.

Methods and devices for signal detection and channel estimation, and associated computer program

A pilot sequence includes pilot vectors to be transmitted in a communication channel. A method of determining the pilot sequence comprises determining an orthogonal basis of a real vector space that is an image of a matrix having, respectively as columns, the partial derivatives of the model vector with respect to the different real parameters; and constructing the pilot vectors using the determined orthogonal basis, by grouping the orthogonal vectors of the orthogonal basis in at least one pair and by producing, for each of the at least one pair comprising a first vector and a second vector, a pilot vector by summation of the first vector and a product of the second vector by an imaginary number.

Method and device for determining a pilot sequence, associated method for estimating a channel and computer program

A digital interpolation filter delivering a series of output samples approximating a signal x(t) at sampling instants of the form (n+d)T s based on a series of input samples of the signal x(t) taken at sampling instants of the form nT s. Such a filter implements a transfer function in the Z-transform domain, H c&#x3c;i/&#x3e;d (Z&#x2212;1), expressed as a linear combination between: a first transfer function H 1 d&#x3c;i/&#x3e;(Z&#x2212;1) representing a Lagrange polynomial interpolation of the input samples implemented according to a Newton structure (); and a second transfer function H 2 d (Z&#x2212;1) representing another polynomial interpolation of the input samples implemented according to another structure comprising at least the Newton structure; the linear combination being a function of at least one real combination parameter c.

Digital interpolation filter, corresponding rhythm changing device and receiving equipment

A method for estimating a wireless communication channel between a transmitter and a receiver, including a plurality of paths for propagation of a wave, at least one of the transmitter and the receiver being formed of a plurality of antennas. The method includes: for at least one path, determining a characteristic matrix, which depends on a first element representative of at least one propagation direction associated with the path, and a second element representative of a propagation distance associated with the path; and estimating the communication channel from the at least one obtained characteristic matrix.

Method for estimating a wireless communication channel, device for estimating a wireless communication channel and computer program therefor

A method for generating a pulse-position-modulated signal. The signal includes a temporal succession of waveforms among Ns waveforms obtained by time shift that is an integer multiple of an elementary time duration Tc. The method includes the following steps executed for a k rank symbol among Ns symbols: obtaining, a set of N modulation coefficients c, a modulation coefficient of index n, c, being expressed as the product of a reference modulation coefficient ccoming from the Fourier series decomposition of a reference waveform associated with a symbol of rank r multiplied by a phase shift term the argument of which is proportional to n; and generating M temporal samples of a k-th waveform carrying the symbol of rank k by Fourier transformation of said set of N modulation coefficients c.

Method for generating a pulse-position-modulated signal, demodulation method and corresponding computer program product and devices

A method for demodulating a received signal resulting from the modulation of a basic chirp signal including estimating of a symbol carried by the received signal, implementing the following sub-steps: determining N decision components from the received signal and from a reference chirp signal obtained by modulating the basic chirp signal by a reference symbol corresponding to a symbol of rank r, a decision component of index I, denoted as a component D, being a function of a term, the phase of which depends quadratically on I, with I being an integer from 0 to N&#x2212;1; and deciding the rank {circumflex over (k)} of the symbol carried by the received signal, from the decision component, of index k, denoted as a component D, having an extremum value among the N decision components.

Method for demodulating a received signal, corresponding computer program and device

A method for processing information representative of a transmission channel between a radio transmitter and a radio receiver. The information includes a matrix representative of the transmission channel. The method includes obtaining at least one pair of eigencharacteristics of the product of the conjugate transpose of the channel matrix with the channel matrix, consisting of non-zero eigenvalues; obtaining a measurement of a signal to noise ratio in the transmission channel; calculating at least one eigenvalue of an autocorrelation matrix of the symbols on transmission, according to a criterion of maximizing a capacity of the transmission channel, from the eigenvalues obtained; and transmitting to the radio transmitter information representative of the at least one calculated non-zero eigenvalue associated with the eigenvector.

Method for processing information representative of a transmission channel by a radio equipment device, receiving equipment and associated computer program

Device for compensating a DC component inherent in any radio frequency chain in which from a single measurement, generally obtained from a digital stage, a set of multiple compensation values is determined by a compensation value vector generating module and which compensation values are applied to multiple compensation points of the analog chain. The compensation values are calculated by an iterative process converging toward cancellation of the DC component and avoid saturating amplification components and components of the analog-to-digital converter. The module includes compensation value calculation units each configured to calculate a respective compensation value and provide the calculated compensation value to the respective compensation point.

Apparatus for removing DC components inherent in a radio frequency chain

A procedure for compensating the DC component inherent in any radio frequency chain making it possible from a single measurement, generally located in the digital stage, to determine a set of multiple compensation values that must be applied to multiple compensation points of the analogue chain. The compensation values are calculated by an iterative process converging towards a cancellation of the DC component and avoid saturating amplification components and components of the analogue digital converter.

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Rennes, France

Stéphane Paquelet