Constructions for finite-state codes
Abstract
A class of codes called finite-state (FS) codes is defined and investigated. These codes, which generalize both block and convolutional codes, are defined by their encoders, which are finite-state machines with parallel inputs and outputs. A family of upper bounds on the free distance of a given FS code is derived from known upper bounds on the minimum distance of block codes. A general construction for FS codes is then given, based on the idea of partitioning a given linear block into cosets of one of its subcodes, and it is shown that in many cases the FS codes constructed in this way have a d sub free which is as large as possible. These codes are found without the need for lengthy computer searches, and have potential applications for future deep-space coding systems. The issue of catastropic error propagation (CEP) for FS codes is also investigated.
- Publication:
-
The Telecommunications and Data Acquisition Report
- Pub Date:
- August 1987
- Bibcode:
- 1987tdar.nasa...42P
- Keywords:
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- Computer Programs;
- Error Correcting Codes;
- Graph Theory;
- Algorithms;
- Coders;
- Spacecraft Communication;
- Theorems;
- Communications and Radar