Experimental investigation of the effectiveness of flow-through modules for electronics cooling

Abstract

Recently installed equipment in naval receiving sites such as digital telephone switching systems, uninterruptible power supplies, laser printers etc. , induce Electromagnetic Interference (EMI) into receiver systems, thus limiting the performance of the receiving site. EMI is injected into receiver systems by conducted, inductive and capacitive paths associated with poor compartment shielding, grounds, or cable shielding. In this thesis, the MITEL SX-20 automatic digital telephone switching system is studied as an EMI source. Temporal and spectral properties of EMI generated by the MITEL SX-20 system are examined over a frequency range of 0 to 100 MHz. The effectiveness of a Barrier, Filter and Ground architecture in containing/eliminating the generated EMI is tested under various operating conditions. Possible solutions are proposed for similar EMI sources.