Iterative Receiver Design
Exploiting the power of factor graphs, this detailed text provides a general framework for systematically developing iterative algorithms for digital receivers, and highlights connections between important algorithms.
TABLE OF CONTENTS Iterative Receiver Design
8.5: Low-Density Parity-Check Codes
8.5 Low-Density Parity-Check Codes
8.5.1 Description
Low-density parity-check (LDPC) codes are a class of codes whose parity-check matrices are sparse in the sense that they contain very few ones per column. They are generally created starting from a sparse parity-check matrix H, from which we then derive a systematic generator matrix G [46, 87]. In this section we will cover how LDPC codes are created, what their factor graphs look like, and how they are decoded using the SPA. As with RA codes, we will work with a running example. We start from a parity-check matrix H given by
Algorithm 8.1: Decoding RA codes: forward backward phase
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