Abstract:
First and second memory means (4,5) are used as buffers during de-interleaving of data. Interleaved data is written into one memory means (4,5) while data is read from the other memory means (4,5) in a de-interleaving manner. A write address generating means (1) generates addresses for storing input interleaved data. A read address generating means (6) generates addresses for reading out data from the memory means (4,5) in a de-interleaved manner. De-interleaving is achieved by applying the read address signals to the memory means (4,5) left shifted by three places relative to the write address signals. A selector means (8) is provided to selectively apply the write address signals and the read address signals to the memory means (4,5).
Abstract:
The detection and correction of errors in digital data transmitted by or stored in a media channel is provided by processing the data through a triple orthogonally interleaved error correction system. On the transmit/store side of the system, the data is encoded three times prior to placement in the media channel with two different interleaving steps performed between the encoding steps. The first interleave is an orthogonal row shuffling interleave that provides enhanced protection against burst errors. On the receive/play back side, the data is decoded and deinterleaved, with included errors detected and corrected to enable recovery of the original data. To enhance the error correction, a circuit is used for generating a symbol accurate error flag identifying symbols containing errors thereby allowing the error correcting decoders to focus on and correct the data.
Abstract:
A wireless communication method implemented in a communication system includes receiving a first data sequence, and processing the first data sequence to obtain information containing at least one of a first number and a sampling spacing associated with the first data sequence. The method also includes permuting the first data sequence to generate a permuted second data sequence. Permuting the first data sequence includes determining a first parameter based on at least one of the first number and the sampling spacing, determining a second parameter based on at least one of the first parameter, the first number, and the sampling spacing, and determining a mapping relationship between a j-th data item of the permuted second data sequence and an i-th data item of the first data sequence. The method further includes outputting the permuted second data sequence.
Abstract:
A 2-dimensional interleaving method is disclosed. The method comprises dividing a frame of input information bits into a plurality of groups and sequentially storing the divided groups in a memory; permuting the information bits of the groups according to a given rule and shifting an information bit existing at the last position of the last group to a position preceding the last position; and selecting the groups according to a predetermined order, and selecting one of the information bits in the selected group.
Abstract:
The present disclosure concerns an interleaver according to the 3GPP-LTE standard turbo interleaving function whereby interleaved bit sequence locations are generated from successive bit sequence locations of a bit sequence. The interleaved bit location is derived iteratively using a new first counter value of a first counter based on a current value of the first counter and a first function derived from an interleaver bit sequence function which relates an interleaved bit sequence location to a bit sequence location. A new second counter value of a second counter is then derived based on a current value of the second counter and the first counter. Finally, an interleaved bit sequence location is output based on the value of the second counter.
Abstract:
Interleaver zum Verwürfeln eines Informationswortes, wobei das Informationswort eine Vielzahl von Stellen aufweist, um ein permutiertes Informationswort zu erhalten. Der Interleaver umfasst eine erste Interleaverstufe zum zeilenweisen Anordnen der Stellen des Informationswortes in einer Mehrzahl von ersten Zeilen und ersten Spalten und eine zweite Interleaverstufe zum Verwürfeln der Stellen einer der ersten Zeilen durch vertauschen wenigstens zweier Stellen der einen ersten Zeile, um eine erste verwürfelte Zeile zu erhalten, und zum Ersetzen der einen der ersten Zeilen mit der ersten verwürfelten Zeile. Die erste Interleaverstufe ist ausgebildet, um die basierend auf der ersten verwürfelten Zeile ersetzte erste Zeile spaltenweise auszulesen, um das permutierte Informationswort zu erhalten.
Abstract:
A de-interleaver generates a plurality of De-interleaved Reorder Physical (DRP) addresses to simultaneously write a corresponding plurality of LLR values into a multi-banked memory such that not more than one LLR value is written into each bank of the multi-banked memory at a time. A sequence of such parallel writes results in the LLR values of a transmission of a sub-packet being stored in the memory. Address translation performed during generation of the DRP addresses causes the LLR values to be stored within the banks such that a decoder can read LLR values out of the memory in a de-interleaved sequence. Each memory location of a bank is a word-location for storing multiple related LLR values, where one LLR value is stored along with its parity values. The ability to simultaneously write to multiple LLR values is used to clear locations in a fast and efficient manner.
Abstract:
A data processing apparatus is operable to map data symbols received from sub-carrier signals of Orthogonal Frequency Division Multiplexed (OFDM) symbols into an output data stream. The data processing apparatus includes an address generator, an interleaver memory and a controller. The controller is operable, when operating in accordance with an even interleaving process to read out from the interleaver memory a first set of the data symbols into the output data stream using addresses generated by the address generator, to write into the interleaver memory a second set of the data symbols received from the sub-carrier signals of an even OFDM symbol using the addresses generated by the address generator. The controller is operable in accordance with an odd interleaving process, to read out from the interleaver memory a first set of the data symbols into the output data stream using read addresses determined in accordance with a sequential order of the first set of data symbols, and to write into the interleaver memory a second set of the data symbols received from the sub-carrier signals of an odd OFDM symbol at write addresses determined in accordance with a sequential order of the first set of input data symbols, such that while data symbols from the first set are being read from locations in the interleaver memory, input data symbols from the second set can be written to the locations just read from. The number of the sub-carriers which are available from a previous OFDM symbol is different from the number of the sub-carriers which are available from a current OFDM symbol, and the controller is operable to determine before reading out the first data symbols from the interleaver memory, whether the read address is valid for the previous OFDM symbol, and to determine before writing the second data symbols into the interleaver memory, whether the write address is valid for the current OFDM symbol. Application can be found with DVB Cable 2, which can provide substantially four thousand carriers.
Abstract:
A method of and apparatus for matching a rate of data bits, in a matrix of data bits interleaved by a predetermined interleaving process (50, 53, 62), to a desired rate by deletion of redundant data bits or repetition of data bits derived from the matrix, includes steps of determining (70) in a non-interleaved matrix of the data bits a pattern of bits to be deleted or repeated to provide the desired data rate, decoding (72) an address of each bit in said pattern in a manner inverse to the interleaving process to produce a respective address of the bit in the matrix of interleaved data bits, and deleting or repeating (76) the respective bit in the interleaved data bits in dependence upon the respective address. The address decoding is performed in the same manner as a coding (53) of addresses for producing the interleaved data bits from the non-interleaved matrix of the data bits. Also disclosed is an advantageous interleaving process for channel interleaving in a 3rd generation CDMA wireless communications system, a shuffling method for a second stage of interleaving in such a system, and how the rate matching can be conveniently applied to turbo-coded data coded.