Canon Kabushiki Kaisha

Frédérique Ehrmann

Philippe Le Bars

François Thoumy

Samuel Rousselin

Lionel Le Scolan

Patrice Nezou

Pascal Rousseau

Félix Henry

Mohamed Braneci

In order to evaluate the noise related to data issuing from a turbo-encoder, estimates of the noise related to its systematic output, to the data issuing from its first elementary encoder, and to the data issuing from its second elementary encoder are determined. At least two of the estimates of the noise related to the systematic output, to the data issuing from the first encoder, and to the data issuing from the second encoder, are added. The results of these additions are divided by the number of augends added, and then inverted, so as to obtain a noise factor, and the noise factor is multiplied with the data issuing from at least one of the first encoder, second encoder, and systematic output.

Method and device for evaluating the noise associated with turbocodes, and systems using them

An original information sequence is encoded by a use of an error correcting code. There is associated with the encoded sequence K frequency symbols in a space consisting of a series of 2increasing frequencies, each of the K symbols representing N encoded symbols, with p, K and N being strictly positive integers. There is applied to the K symbols a reversible transformation including a multiplication by an invertible matrix of size N&#xd7;N, and signals obtained from the inverse transform signals are sent. There exists a K-tuplet of positive integers n, n, . . . , nat least one of which is strictly positive, such that, for an integer I varying from 1 to K, after periodic extraction of one frequency out of 2among the frequencies of the iof the K symbols, thus forming a reduced frequency symbol of 2frequencies, K reduced frequency symbols are obtained, representing the original information sequence, with a view to complete or partial decoding.

Methods and devices for sending and receiving information, and systems using them

The method of transmitting data in the form of symbols sent over an electromagnetic channel is characterized in that a measurement of significance is attributed to each group of data to be transmitted, in that the transmission reliability of the carriers is estimated dynamically, and in that the most significant data are sent over the most reliable carriers at each instant, the other data being sent over the carriers of decreasing reliability, in decreasing order of significance of the data.

Device and method for the dynamic allocation of frequencies for multicarrier modulation systems

The invention concerns a method of adjusting at least one parameter for the compression of data representing physical quantities, the compressed data then being coded according to a coding mode in order to protect it from transmission errors. The methods includes, as from a required compressed data size, determining at least one characteristic of the coding mode, determining an effective size of the compressed data according to the required size and the at least one characteristic, and adjusting at least one compression parameter according to the effective size.

Compression of digital data and coding of the compressed data in order to protect them against transmission errors

The present invention concerns a method and an apparatus of generating a reference event in a receiving node receiving frames of information, when a frame of information is received, the method and the apparatus sample the frame of information in order to form sampled data, process sampled data in order to detect among said sampled data a specific data, monitor the number of processed sampled data until the detection of a specific data and generate a reference event according to the result of processing and monitoring.

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Rennes, France

Frédérique Ehrmann