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Wide-Sense Time-Invariant Block Codes in Their Parity Check Matrix

  • Giovanni CancellieriEmail author
Chapter
Part of the Signals and Communication Technology book series (SCT)

Abstract

A wide-sense time-invariant block code in its parity check matrix exhibits more than one parity check polynomial periodically repeating. Quasi-cyclic codes are revisited from this point of view. Reordered forms of quasi-cyclic codes are treated. Shortening or lengthening, with respect to the quasi-cyclic condition, are possible here only with steps of integer periods. The concept of code duality is extended. Code puncturation is described for quasi-cyclic codes. Constant-length shortening and constant-length puncturation are dual operations by which an information symbol is transformed into a control symbols and vice versa. Modified lengthening and modified H-extension are discussed also for quasi-cyclic codes. Encoder circuits, state diagrams and trellises are finally outlined.

Keywords

LDPC Code Parity Check Code Word Cyclic Code Convolutional Code 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Information EngineeringPolytechnic University of MarcheAnconaItaly

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