Alcatel

Elie Bejjani

Alexandre Da Rocha

Jean-Hugues Perrin

Jean-Fran&ccedil;ois Bouquier

Beno&icirc ;t De Cacqueray

Benoit De Cacqueray

Jean-Francois Bouquier

Javier Sanchez Araujo

Celine Durand

Beno&icirc;t De Cacqueray

The invention relates notably to a method for modulating information symbols to be transmitted in a CDMA communication network by using a non-orthogonal modulation code comprising M spreading sequences (s1&#x2266;m&#x2266;M), each comprising in N chips (s1&#x2266;n&#x2266;N), the M spreading sequences having the same energy. According to the invention, the amplitude of the chips take a plurality of values the number M of spreading sequences is higher than the number of chips N per spreading sequence.

Correlated spreading sequences for high rate non-coherent communication systems

The invention relates to a method for synchronizing a radio terminal in a radio-communication network with a received signal flow comprising a predefined synchronization sequence repeated at predefined time intervals. According to the invention, the method consists in generating correlation profiles at the radio terminal by correlating a part of said signal flow with the synchronization sequence to reveal correlation peaks and accumulating as many correlation profiles as necessary, until a threshold level is reached by at least the largest correlation peak. The threshold level is updated, during the accumulation, depending on a background noise level estimated in the signal flow to dynamically determine if the synchronization sequence has been detected at the radio terminal.

Method of synchronizing a radio terminal of a radio communication network and a corresponding radio terminal

Path selection method in a CDMA receiver for the selection of the true path of a transmission channel, comprising the step of comparing the profile energy with a threshold, characterized in that the threshold is dynamically determined as a function of the mean of noise and interference paths derived from the transmission channel profile estimation.

Adaptive path searcher in a CDMA receiver

Receiver for enhanced performance for CDMA radio transmission comprising roke receiver with a path searcher ( ), a channel estimator ( ) and a combiner ( ) for selecting optimal paths where the path searcher selects a set of path delays ( ) with an instantaneous profile analyzer ( ), an averaging filter ( ) and a path selector ( ) where at least two instantaneous profile analyzers ( ) are connected to the averaging filter ( ).

Receiver and method with enhanced performance for CDMA transmission

Receiver for enhanced performance for CDMA radio transmission comprising a Rake receiver ( ) with a path searcher ( ), a channel estimator ( ) and a combiner ( ) for selecting optimal channels paths where the path searcher ( ) selects a set of path delays ( ) where at least two path searchers ( ) are connected in way that the output of the first path searcher ( ) is linked to one input of the second path searcher ( ).

Receiver and method for CDMA transmission with enhanced path searcher

The invention relates to a telecommunication method, wherein: terminals communicate through a central station, uplink and downlink communications are coded with a spread spectrum sequence, and terminals have different powers. At the central station, interference cancellation is performed in order to reduce the interfering effect of the highest power signals on the detected lowest power signals. In this method, at least for some of the most powerful interfering signals, groups of symbols (TS,, TS,) of different interfering signals are time aligned when they reach the central station. Preferably, the synchronized groups of symbols are synchronously detected at the central station and are processed jointly prior to be subtracted from the signal to be detected.

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Saint-Cloud, France

Elie Bejjani