EMP Hardening and Assessment of a Terrestrial Communications System

The National Communication System funded, and the Defense Nuclear Agency administered, a contract with AT&T to develop an EMP hardened version of the T1 transmission system. This paper discusses the approach used to develop the hardened version of the T1 System, including a description of the EMP hardening philosophy, interpretation of the test results, and the integrated system assessment. The results of the program indicated that for the route studied, augmented electrical shielding and the application of terminal protection devices will provide an EMP-hard terrestrial common-carrier transmission system.