Communications Blockset

Convolutional Coding

Convolutional coding is a special case of error-control coding. Unlike a block coder, a convolutional coder is not a memoryless device. Even though a convolutional coder accepts a fixed number of message symbols and produces a fixed number of code symbols, its computations depend not only on the current set of input symbols but on some of the previous input symbols.

Organization of This Section

• Describes how to access the Convolutional sublibrary of Error Detection and Correction
• Summarizes the software's capabilities
• Discusses parameters for convolutional coding (polynomial description and trellis description)
• Illustrates the use of the coding blocks for a rate 2/3 code
• Explains how to implement a systematic encoder
• Illustrates soft-decision decoding

For background material on the subject of convolutional coding, see the works listed in Selected Bibliography for Convolutional Coding.

Selected Bibliography for Block Coding

Accessing Convolutional Coding Blocks