Patent ID: 7506220

Claim:
A method for de-interleaving S 2 received sequences of interleaved received data samples respectively issued from S 2 physical channels and to be associated with S 1 output transport channels, the S 2 received sequences having been delivered, before transmission by a two-stage multi-interleaving device, from S 1 initial sequences of ordered data samples respectively associated to S 1 initial transport channels, the two-stage multi-interleaving device comprising a first stage including S 1 interleaving blocks respectively associated with the S 1 initial transport channels, a second stage including S 2 interleaving blocks respectively associated with the S 2 physical channels and an inter-stage of predetermined data-routing functions connected between the first and second stages, the method comprising: a) for each of the S 2 received sequences, determining for each output transport channel a number N s 2 co1(s 1 ) of received data samples of the sequence belonging to the output transport channel, and calculating for each received data sample belonging to the output transport channel, its rank in the sequence of data samples associated with the output transport channel, the rank being identical to the rank of the corresponding data sample in a corresponding initial sequence associated with the corresponding initial transport channel, where s 1 specifies a range of first stage interleaving blocks and a range of initial transport channels, s 2 specifies a range of second stage interleaving blocks and a range of physical channels, and col(s 1 ) corresponds to a number of columns of the second stage interleaving blocks, wherein calculating the rank of a received data sample comprises calculating a phase term depending on a column range (n 2 ) of the second stage interleaving blocks associated to the physical channel and on a column range (n 1 ) of the first stage interleaving blocks, and for a received sequence associated to a determined physical channel, a1) successively calculating different values of the phase term for different values of n 1 , and a2) repeating step a1) a number of times equal to the number of columns of the second stage interleaving block, with a value of n 2 being different at each repetition; b) storing each data for which its rank has been calculated, in a memory element associated with the corresponding output transport channel, taking into account its calculated rank; and c) when all the S 2 received sequences have been processed, reading each memory element such that stored data samples are successively read in the same order as the order of the initial sequences of ordered data samples.