Commissariat a L'energie Atomique

Xantima LLC

Christophe Boulanger

Laurent Ouvry

Bernard Piaget

Didier Lattard

Charles Fort

Jean-René Lequepeys

Didier Varreau

Mathieu Bouvier Des Noes

Laurent Herault

Roselino Lionti

A method of parallel suppression of interference, and corresponding stage and receiver is disclosed according to the invention, parallel suppression of interference is carried out starting from the signals selected by a maximum likelihood criterion based on the calculation of a metric and the search for the smallest possible metric.

Method of receiving CDMA signals with parallel interference suppression, and corresponding stage and receiver

A method for receiving spectrum spreading signals using a Doppler-effect frequency-shift correction generates a corrective signal based on an estimation of a modulation period related to the Doppler effect detected in a preamble portion of a received signal. The corrective signal is used for correcting an information portion of the received signal. Base band digital signals are operated upon by using the DOT and CROSS components.

Method for receiving spectrum spreading signals with frequency shift correction

The present invention relates to a method for receiving CDMA signals with synchronization being obtained through double delayed multiplication, and an associated receiver. According to the invention, the correlation signal undergoes double delayed multiplication. Synchronization is established on the signal thus generated. Applied to digital communications, in particular with mobile phones.

Method for receiving CDMA signals with synchronization resulting from delayed double multiplication and corresponding receiver

A method for receiving spectrum spreading signals with frequency shift correct in which the modulation period related to the Doppler effect is estimated by using a preamble and a correction signal is elaborated, the signal transmitting the information is then corrected by this correction signal.

Method for receiving spectrum spread signals with frequency offset correction

A CDMA receiver with parallel interference suppression and with weighting. The weighting coefficients of the outputs from the various stages of the receiver are chosen in order to minimize a quadratic error weighted by the distribution of the pertinent values of the intercorrelation matrix.

CDMA receiver with parallel interference suppression and with weighting

A method for processing a direct sequence spread spectrum signal, and a receiver for performing the method. A correlation is preformed between a received signal and the direct sequence used to determine peaks of different amplitudes. The spectrum of the information corresponding to the highest amplitude peak is respread using the direct sequence. The respread signal is subtracted from the received signal to create a new signal. This process is reiterated on the new signal until all of the peaks have been exhausted.

Process for the processing of an information transmission signal by spread spectrum and the corresponding receiver

Direct sequence spread spectrum transmission process that generates and optimizes sequences used by respective users of a communications system. A set of random sequences is produced and the sequences are optimized by a combinatorial operation in order to minimize residual noise. The random sequences belong to an M.sup.th set of roots unity, where respective of the N random sequences have given length L.

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Ivry-sur-Seine, France

Christophe Boulanger