Convolutional coding for channels with memory

Abstract

This paper discusses the use of two types of convolutional codes, diffuse threshold-decoded codes and Gallager codes, on channels with memory (burst channels). The operation of these codes is explained and test results are given for a variety of equipments operated over phone line, HF radio, and troposcatter channels. Error propagation in the threshold-decoded codes is discussed and, in the Appendix, we prove that, for one important diffuse code, propagation is finite and small.