Computer Determination of Electromagnetic Wave Shielding Effectiveness

The author has developed a technique for rapid determination of the shielding effectiveness of any metal through use of the IBM remote access computing system (RAX). RAX consists of one central computer and numerous control terminals placed throughout Bell Aerosystems engineering areas. To obtain a matrix of shielding information versus frequency the engineer activates his terminal, inserts his program from the library file, and supplies the desired metal thickness, conductivity, permeability, and test distance. The terminal then prints a table of shielding effectiveness. The entire process can be accomplished in about four minutes. This paper includes several samples of output data, lists the program which was used, and shows how the engineer communicates with the machine to obtain the desired output.