Error Control Coding For B3G/4G Wireless Systems: Paving the Way to IMT-Advanced Standards

Chapter 1

Coding

Gerhard Bauch¹, Claude Berrou,² David Declercq,³ Alexandre Graell I Amat,² Youssouf Ould-Cheikh-Mouhamedou,⁴ Yannick Saouter,² Jossy Sayir,⁵ and Marcos B.S. Tavares⁶

¹Universität der Bundeswehr Munich, Germany

²Telecom Bretagne, France

³ETIS ENSEA/Université de Cergy-Pontoise/CNRS, France

⁴King Saud University, Saudi Arabia (formerly with Telecom Bretagne, France)

⁵Cambridge University, United Kingdom

⁶Technische Universität Dresden, Vodafone Chair, Germany

1.1 General Code Types

The most important coding schemes that can be decoded using an iterative (turbo) algorithm can be classified as parallel concatenated codes, serial concatenated codes and low-density parity check (LDPC) codes as indicated in Figure 1.1.

Figure 1.1 Coding schemes with iterative decoding

In parallel concatenated codes, the data sequence is encoded by the first constituent encoder. The second constituent encoder encodes an interleaved version of the data sequence. The data bits are sent only once as systematic bits of the concatenated code, whereas only the parity bits of the constituent encoders are transmitted. Usually, recursive systematic convolutional codes are used as constituent codes. However, other code types, for example block codes, can be used and more than two constituent codes can be concatenated with different interleavers. Parallel concatenated convolutional codes (PCCC) ...