Citation
Abstract
In this article 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 code into cosets of one of its subcodes, and it is shown that in many cases the FS codes constructed in this way have ad free which is as large as possible. These codes are found without the need for lengthy computer searches, and have potential applications to future deep-space coding systems. The issue of catastrophic error propagation (CEP) for FS codes is also discussed, and it is found that, in order to avoid CEP, one must solve a very interesting problem in graph theory, the problem of finding a noncatastrophic edge-labeling of the state diagram.
Details
- Volume
- 42-90
- Published
- August 15, 1987
- Pages
- 42–49
- File Size
- 685.1 KB