Use of the APL Computer Language to simulate communications channels with low signal to noise ratios

This thesis demonstrates the use of the APL computer language as a tool for communications engineers to use in the simulation of noisy communications channels. With this ability, the engineer may examine the effectiveness of various error-correcting-codes. Programs are written for several block and convolutional codes. These programs are used to encode and decode messages on a channel with bit-error-rates of 0.25 and 0.1. A comparision is made of various codes and combinations of codes to determine which are most effective in a noisy environment.

The results favor the use of concatenated codes with a repetition code as the outer code and an inner Hamming code. For the lower noise condition, either a Hamming or a convolutional code may be used as the inner code.