On the Many Faces of Block Codes

  • Kaustubh Deshmukh
  • Priti Shankar
  • Amitava Dasgupta
  • B. Sundar Rajan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1770)


Block codes are first viewed as finite state automata represented as trellises. A technique termed subtrellis overlaying is introduced with the object of reducing decoder complexity. Necessary and sufficient conditions for subtrellis overlaying are next derived from the representation of the block code as a group, partitioned into a subgroup and its cosets. Finally a view of the code as a graph permits a combination of two shortest path algorithms to facilitate efficient decoding on an overlayed trellis.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Kaustubh Deshmukh
    • 1
  • Priti Shankar
    • 2
  • Amitava Dasgupta
    • 2
  • B. Sundar Rajan
    • 3
  1. 1.Department of Computer Science and EngineeringIndian Institute of Technology BombayMumbaiIndia
  2. 2.Department of Computer Science and AutomationIndian Institute of ScienceBangaloreIndia
  3. 3.Department of Electrical Communication EngineeringIndian Institute of ScienceBangaloreIndia

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