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Cnam-conservatoire National Des Arts Et Metiers

Cassidian Finland Oy

Cnam Conservatoire National Des Arts Des Metiers

Philippe Mege

Christophe Brutel

Laurent Martinod

Christophe Molko

Olivier Perrin

Luc Fety

Philippe Lucas

Hang Nguyen

Pierre-Yves Le Gal

Gérard Marque-Pucheu

Eric Georgeaux

Marc Delprat

Olivier Gagey

Fabrice Belveze

Marc Mouffron

Alina Alexandra Florea

Nicolas Gregis

Jean-Louis Dornstetter

Stephane Pineau

Alina-Alexandra Florea

Frédéric Rosin

Frederic Rosin

Pierre-Yves Legal

A method allocates radio resources to a plurality of communications in a broadband telecommunication system, each communication being associated with at least one piece of user equipment, at least one of the communications being associated with a single piece of user equipment, the radio resources being distributed according to time and frequency between blocks of resources. The plurality of communications forms at least one group of communications and at least the same block of resources is allocated to the group of communications in order to transmit the plurality of communications.

Method for allocating radio resources in a telecommunications system

A device for processing a received signal by a receiver disrupted by a transmitter, wherein the transmitters and receiver are co-located, includes: a first coupler configured to take a first reference signal; an analog circuit for processing the first reference signal; a second coupler configured to combine the modified reference signal with the signal received by an antenna of the receiver; a first analog-to-digital conversion module digitizing the first reference signal; the second analog conversion module digitizing the combined signal in order to deliver a digital combined signal to the digital signal-processing device, wherein signal-processing device delivers a resulting digital signal to a data-processing module of the receiver device.

Device and method for processing a signal received by a receiver disrupted by a transmitter

A method estimates a channel for radioelectric propagation between a transmitter and a receiver. The transmitter transmits a signal including frames that each use Nfrequency subcarriers, over each of which Nsymbols are transmitted, wherein, among the set of symbols, certain symbols, referred to as pilot symbols, are known to the receiver. The method implemented in the receiver includes; determining an overall intermediate covariance matrix Mof the channel that embodies a time profile of the channel, which profile is symmetrical and centered on the time synchronization position, and a frequency profile of the channel, which profile is symmetrical and centered on the frequency synchronization position; calculating a vector for an intermediate channel C on the basis of the predetermined overall intermediate covariance matrix M; and estimating the channel on the basis of the calculated vector for the intermediate channel C'.

Method for estimating a radioelectric propagation channel

A method for reducing the crest factor of a wideband signal including N narrowband signals, N being a natural integer greater than or equal to two, the method, implemented by an emitting equipment, including phase shifting the narrowband signals between them in such a way as to reduce the crest factor.

Method for reducing the crest factor wide band signal

This interference reduction method in a receiver () comprising at least two antennas (), each receiving a signal transmitted through a radio propagation channel, comprises the following steps: &#x2014;weighting () of each of the signals received with a weighting vector associated respectively with a respective antenna of the receiver; &#x2014;combination () of the weighted signals received to obtain a combined received signal; &#x2014;weighting () of a reference signal with another weighting vector; &#x2014;comparison () of the combined received signal and the weighted reference signal to obtain an error; and &#x2014;determination () of the weighting vectors with the help of the maximum a posteriori criterion by maximizing the probability of realization of the said weighting vectors conditionally with the error obtained.

Interference reduction method

A method for demodulating a signal in a receiver including at least two antennas, each receiving a signal, the received signals corresponding to a single emitted signal including symbol frames in which certain symbols, referred to as driver symbols, are known to the receiver, the method including: noise whitening in order to form two combined signals, the noise components of which are separate; normalizing the noise components of the combined signals in order to form two signals, the noise components of which are separate and have equal average standards; and performing signal demodulation with the maximum combination of the signal-to-noise ratio on the two signals, the noise components of which are separate and which have equal average standards, wherein during the first noise-whitening step for forming the two combined signals, the latter are determined retroactively using the maximum criterion.

Method for demodulating a signal

This transmission comprising a first transmission of a packet (), comprising the steps consisting in: a first processing () of said packet () to obtain a first packet (); and a coding () of the first packet (); wherein, when the first coded packet is received erroneous, the method comprises a second transmission of said packet, comprising: the steps implemented in the transmitter, consisting in: a second processing () of said packet () to obtain a second packet (); and a coding () of the second packet (); and the steps implemented in the receiver, consisting in: a modification of the first and/or the second coded packets to obtain two packets in which the difference due to the first and second processings is compensated for: a combination () of both packets according to a HARQ procedure; and a decoding () of the combined packet.

Data packet transmission method

A method of management for operating a first system of communication of the broadband type communication system emitting over a first frequency range, and a second system of communication of the narrow band type communication system emitting over a second frequency range, the first system and the second system using all or part of a same frequency band, such common frequency band being called a crossover frequency band for both systems, the method including: embodying a scan operation from at least the crossover frequency band of the two systems using a scan device from the first communication system; identifying, after the scan operation, the frequency channels used by the second communication system; adapting the operating of the first communication system within the frequency channels identified as being used by the second communication system.

Method of management for operating a broad band communication system and a narrow band communication system implemented in a same frequency band

An error correction encoding method is provided for encoding source digital data having the form of a frame, wherein the data can be classified into a plurality of classes. The present encoding method includes the following steps: Related decoding methods, as well as encoding and decoding devices are also disclosed.

Error correction encoding method, decoding method and associated devices

This method for the estimation of a channel between an emitter and a receiver, where the said emitter emits a signal comprising symbol frames distributed in time and frequency, among which pilot symbols known to the receiver, is characterized in that it comprises the following steps: &#x2022;&#x2014;computation () of a covariance matrix Mand Mof the channel in the frequency and time domains respectively; &#x2022;&#x2014;decomposition () of the covariance matrices Mand Minto eigenvectors according to the relations M&#x2212;WNWand M&#x2212;WNW; &#x2022;&#x2014;computation () of the Kronecker product of the matrices NVand Wto obtain an eigenvector matrix W; &#x2022;&#x2014;computation () of a diagonal eigenvalue matrixequal to the Kronecker product of the eigenvalue matrices Nand N; and &#x2022;&#x2014;estimation of the channel with the help of pilot symbols and matrices W and N using the maximum a posteriori or quadratic error minimisation criterion.

Method for estimating a radio channel

An emission chain, comprising a processing pathway for an input signal which includes a digital signal decomposition according to N signal components, with N an integer greater than or equal to 2. The N signal components being converted from a digital form into an analog form and following distinct physical pathways that induce first respective delays on the N signal components. A delayed input signal is obtained by applying a second delay (&#x3c4;) having a value greater than or equal to the maximum value of the first delays. Next, N correction delays (&#x3c4;&#x2212;&#x3c4;) are applied respectively to the N signal components based on a comparison between said input signal delayed by the second delay and the signal to be emitted. Finally, the signal to be provided to a power amplifier is obtained by combining the N signal components obtained on completion of the previous step.

Correction of distortions in an emission chain

To reduce interferences in signals received by a receiver through a propagation channel, each including symbols distributed according to frequency and time dimensions and corresponding to a common emitted signal, the receiver weights an estimate of the emitted signal and the received signals by weighting vectors evolving in vector subspaces representing time variations and frequency variations of the channels for propagating the signals between an emitter and the receiver. These vector subspaces are defined by matrices, some columns of which are suppressed as a function of frequency and time constraints of the channel. The receiver minimizes a function of the difference between the sum of weighted received signals and the weighted estimate of the emitted signal in order to estimate the emitted signal as a function of the weighting vectors and the received signals.

Reduction of interference in an OFDM signal with weighting vectors evolving in vector subspaces

A radio communication emitter includes at least two antennas for emitting a signal including encoded bits that are converted into symbols distributed on subcarriers and in time intervals. The emitter includes a signal divider for distributing the set of the signal symbols into as many disjoined subsets of signal symbols as the antennas that the emitter comprises. Each subset is dedicated to one of the antennas. The union of the subsets is the set of the signal symbols. Symbols are distributed in at least two subsets for at least one time interval or for at least one subcarrier of the signal. The antennas synchronously emit the symbol subsets. The symbol subsets can comprise a substantially identical number of symbols to reduce a deviation between the power peaks and the average power of the signal emitted by each antenna.

Signal emission by plural antennas

A signal is received in a telecommunication network in the form of P signals received on P corresponding antennas, where P is greater than or equal to 1. The received signals correspond to a multi-carrier signal transmitted in the form of flames comprising symbols occupying corresponding positions distributed along a time axis and along a frequency axis; a frame comprising M blocks each having at least N reference symbols. The reference symbols in each of the blocks satisfy a first maximum spacing between each other along the time axis and a second maximum spacing between each other along the frequency axis, less than a first value and a second value respectively, M being an integer number equal to at least two. M estimated noise power values are determined at frame level, each related to one of the M emitted reference symbol blocks. Values of the estimated noise power for the other symbols in the frame are then obtained from the determined estimated noise power values.

Noise power interpolation in a multi-carrier system

A signal is received by P antennas. It includes frames having symbols occupying respective positions distributed along an axis of time and of frequency, a frame including M blocks having N reference symbols M groups of P weighting coefficients are determined, each one of the groups relating to one of the blocks emitted, with the coefficients of a group being associated to the blocks which are received on the P antennas and which correspond to the block emitted relating to the group. The coefficients are determined so as to increase via a threshold value, an error value for each block emitted, between the reference symbols of the block emitted, and the symbols obtained using the symbols received on each antenna at the positions of reference symbols corresponding to the block emitted and the associated coefficients. Then, weighting coefficients are obtained for the other symbols of the frame Finally, a composite signal is generated by summing up the symbols received respectively weighted by the associated weighting coefficients.

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Bourg la Reine, France

Philippe Mege