CODING FOR IMPROVED COMMUNICATIONS

This chapter discusses various forms of baseband pulse code modulation (PCM). It introduces variety of important coding‐related topics: gray coding, differential coding, pseudo‐random noise (PRN) sequences, binary cyclic codes, cyclic redundancy check (CRC) codes, data randomizing, or scrambling and data interleaving. The chapter discusses several forms of FEC channel coding: Wagner coding and decoding, convolutional coding and Viterbi decoding, turbo codes (TCs), parallel concatenated convolutional codes (CCCs) (PCCCs), serially CCCs (SCCCs), double parallel CCCs (DPCCCs), and double serially CCCs (DSCCCs) with reference to the related hybrid CCCs (HCCCs), and self‐concatenated codes (SCCs). It also introduces low‐density parity‐check (LDPC) codes, product codes (PCs), and turbo product codes (TPCs) and discusses Bose–Chaudhuri–Hocquenghem (BCH) codes, including M‐ary Reed–Solomon (RS) codes and RS Viterbi (RSV) codes. In practice, the RSV code typically uses an interleaver between the inner and outer codes to improve the decoding reliability.