Advanced Cable Shield Termination Process for Broad-Band EMI Suppression

This paper deals with the design progression, qualifi­ cation, and application of an advanced cable-toconnector termination process for circular connectors. The design includes a method for terminating backshells, and cables constructed of individually shielded conductors with overall shields. This project was initiated because of recently defined operational requirements and the critical need to redesign shielded cable to connector terminations. The objective of this project was to design and develop a shielded cable-to-connector termination that would combine a high level of broad-band electro­ magnetic shielding, superior mechanical characteris­ tics, ease of assembly, and cost effectiveness. In pursuit of the stated objectives the design produced broad-band attenuation in excess of 120 dB in the frequency range of 100 KHz to 3 GHz, sloping to 90 dB at 10 GHz. The mechanical evaluation produced backshell bending moments and torque resistance in excess of 1000 inch pounds. Dynamic loading of 40 G random for eight hours in each axis produced no degradation to the electrical or mechanical character of the backshell to connector interface. The significance of this work lies in the fact that it is possible to terminate shielded cables to connectors and provide the same degree of broad-band attenuation to electro­ magnetic radiation supplied by the connectors themselves.