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LDPC Encoder - Encode binary low-density parity-check code specified by parity-check matrix

Library

Block sublibrary of Error Detection and Correction

Description

This block supports encoding of low-density parity-check (LDPC) codes, which are linear error control codes with sparse parity-check matrices and long block lengths that can attain performance near the Shannon limit.

The LDPC Encoder block uses the same algorithm as the fec.ldpcenc Communications Toolbox object. See LDPC Encoding Method for details.

(n – k) and n are the number of rows and columns, respectively, in the parity-check matrix.

Both the input and the output are discrete-time signals. The ratio of the output sample time to the input sample time is . The input must be a real frame-based signal.

The output inherits the data type of the input, and the input must be binary-valued (0 or 1).

Type commdvbs2 at the command line to see a demo using this block.

Note   Model initialization or update may take a long time, because a large matrix may need to be inverted (when the last (n – k) columns of the parity-check matrix is not triangular).

Dialog Box

Parity-check matrix

This block can accept a sparse matrix with dimension n -k by n (where n >k > 0) of real numbers. All nonzero elements must be equal to 1. The upper bound limit for the value of n is 2³¹-1

The default value is the parity-check matrix of the half-rate LDPC code from the DVB-S.2 standard.

Pair Block

dvbs2ldpc and LDPC Decoder

LDPC Decoder

Linearized Baseband PLL

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