Abstract: The metrics matrix may include at least one particular layer including at least one particular column having several metrics cues, respectively, situated in different rows. For the particular layers the updating of the channel cue is associated with the particular column involving at each iteration one updated metric cue selected from all the metrics cues of the particular column. The row of the selected metric cues may change at each iteration.

Abstract: An interleaver includes two random access memories for storing data and an addressing device (100) linked to respective address inputs of the two memories. The addressing device is designed to transmit, at each instant of a clock, a cue for read access to one of the two memories and a cue for write access to the other of the two memories, so that, at each instant, a data item is written to or read from each memory.

Abstract: An input memory of an LDPC decoder is loaded with data corresponding to an LDPC frame to be decoded and including N LLRs, of which K are information LLRs and N-K are parity LLRs. At least one stream is formed of binary words of a first type, each corresponding to multiple information LLRS, with the aid of a serial/parallel conversion module, and at least one stream is formed of binary words of a second type, each corresponding to multiple parity LLRs, with the aid of a row/column interlacing device comprising a two-dimensional first-in first-out ring buffer. The first memory accesses are made in page mode in order to write the binary words of the first type to a first zone of the input memory, and the second memory accesses are made in page mode in order to write the binary words of the second type to a second zone.

Abstract: A concatenated channel decoding method wherein the bits of a set of N1 bits decoded using a first iterative block decoding algorithm and intended to be decoded using a second block decoding algorithm, are sent in parallel in at least one subset of P bits to a buffer for temporary storage. The decoding method comprises receiving in parallel at least one subset of Q bits belonging to the set of N1 bits sent to the buffer, detecting errors with the help of the second decoding algorithm, based on the bits decoded using the first decoding algorithm, and correcting the bits stored in the buffer as a function of possible errors detected. Detecting errors and/or the correcting the stored bits comprise a parallel processing of the bits of each subset of Q bits received.

Abstract: A method for the iterative decoding of a block of bits having a number N of bits to be decoded where N is a whole number greater than or equal to two, using an iterative decoding algorithm, comprises the generation of a current block of N intermediate decision bits by executing an iteration of the decoding algorithm, followed by the verification of a stability criterion for the current block by comparison of the current block with a given block of N reference bits. If the stability criterion is satisfied, the iterations of the iterative decoding algorithm are stopped and the current block of intermediate decision bits is delivered as a block of hard decision bits. Otherwise another iteration of the decoding algorithm is executed.

Abstract: A system implemented for example in the form of an SoC comprises a first demodulator for generating a first data stream to be decoded, and a second demodulator for generating a second data stream to be decoded, and a block decoder. The block decoder comprises an input memory for storing blocks of data from the first data stream and blocks of data from the second data stream, and a block decoding unit for processing, from the input memory, the blocks of data from the first and second data streams.

Abstract: A device for storing blocks of bits intended to be decoded according to a block decoding algorithm. The blocks are likely to belong to a given category out of a first category and a second category. The first category corresponds to a first given block size, and the second category corresponds to at least one second given block size less than said first block size. Said storage device comprises three storage elements having a size suitable for storing one block of the first category each, and at least two of which are structured to store either one block of the first category, or one block of the second category or a number of blocks of the second category simultaneously.

Abstract: A barrel shifter receiving N symbols, arranged n2 distinct groups of n1 symbols, applying a circular shift to the N symbols. The barrel shifter comprises n2 first barrel shifters, each applying a first circular shift to one of the groups of n1 symbols; a rearrangement module receiving the N symbols provided by the first barrel shifters and providing N symbols arranged, in a determined manner, in n1 distinct groups of n2 symbols; n1 second barrel shifters, each applying a second circular shift to one of the distinct groups of n2 symbols; a control module providing, to each first barrel shifter, an identical signal bs_ctrl1 representing the first shift, and providing, to each second barrel shifter, an identical signal bs_ctrl2 representing the second shift; and a switching module switching at least two of the symbols of the N symbols.

Abstract: An LDPC decoder comprising processing units capable of receiving first messages and of providing second messages based on the first received messages; first and second single-port memories; and means for reading first words from the first and second memories, each first word containing first messages, providing first messages to the processing units based on the first read words, forming second words, each second word containing second messages provided by the processing units, and writing the second words into the first and second memories, said means being capable of reading a first (respectively second) word from the first memory and of simultaneously writing a second (respectively first) word into the second memory.

Abstract: An LDPC decoder comprising a determined number of processing units operating in parallel, a storage means capable of containing first words containing a juxtaposition of messages of a first type, and second words containing a juxtaposition of messages of a second type, a message provision unit capable of providing each processing unit with a message of the first type or a message of the second type, and a message write unit capable of writing, into the storage means, first words or second words. The message provision unit is capable of providing a message at a position in a word which depends on the word or the message write unit is capable of writing each message at a position in the word which depends on the word.

Abstract: An add-compare-select-offset device including first and second adders for generating values a and b respectively equal to the sum of first previous state and branch metrics and to the sum of second previous state and branch metrics, a calculation block for providing the greatest of values a and b on a first output and generating an adjustment value on a second output; and, a third adder for generating a current state metric equal to the sum of the outputs of the calculation block, wherein the adders perform additions without keeping the carry so that the current state metric and intermediary values a and b comprise the same number of bits as the first and second previous state metrics.

Abstract: An image adapter transforms an input image into an output image by successively processing tiles and by changing numbers of columns and of rows of image points. The image adapter includes queue memories connected in series so as to receive values associated with the points of a tile of the input image. A module for calculating a weighted average possesses inputs connected respectively to an output of one of the memories. The module produces values sampled in a direction parallel to the columns and corresponding to the values associated with points of the input image. A sampling rate converter, connected to the output of the module, produces values associated with the points of the output image according to a sampling rate determined for a direction parallel to the rows.

Abstract: An interleaver includes two random access memories for storing data and an addressing device (100) linked to respective address inputs of the two memories. The addressing device is designed to transmit, at each instant of a clock, a cue for read access to one of the two memories and a cue for write access to the other of the two memories, so that, at each instant, a data item is written to or read from each memory.

Abstract: An add-compare-select-offset device including first and second adders for generating values a and b respectively equal to the sum of first previous state and branch metrics and to the sum of second previous state and branch metrics, a calculation block for providing the greatest of values a and b on a first output and generating an adjustment value on a second output; and, a third adder for generating a current state metric equal to the sum of the outputs of the calculation block, wherein the adders perform additions without keeping the carry so that the current state metric and intermediary values a and b comprise the same number of bits as the first and second previous state metrics.