Errors in Data Transmission Systems

The aims and methods of a program of work being conducted at the Lincoln Laboratory of the Massachusetts Institute of Technology in data-transmission research are discussed. The work, which has been concentrated primarily on telephone circuits of a type generally available, is aimed at a better understanding of these transmission media. Machines for the measurement of error and error distributions occurring in data-transmission channels and machines for recording impulsive-type noise on telephone circuits are described. Some results from both types of measurement are presented. One of the most significant results of this program has been the demonstration that errors occur on telephone circuits in bursts. Among the major sources of errors on telephone circuits is the burst of additive noise. With the machine described above, some success has been achieved in classifying several of the types of burst which occur and in deducing their probable causes.