Effects of Electrical Contact Failure on High Speed Digital Signal Transmission

In digital communication systems, the deleterious effects of contacts at coaxial connector is one of the major causes of declining quality of communication. This paper describes the effects of contact degradation caused by contamination of a coaxial connector on transmitted signal integrity and error code rate. Transmission of high frequency current through degraded coaxial connectors is simulated and analyzed based on finite element method (FEM). An improved contact impedance model is introduced and its influence on high speed signal transmission is investigated. The impedance of degraded coaxial connectors is presented. The phenomena of contact failure which lead to error codes in signal transmission are confirmed in the experiments.