Practical solutions to radiated susceptibility problems (A case history)

The penetration of Electromagnetic (EM) Energy through the compromised shielding integrity entry points of an enclosure may result in the catastrophic failure of the vital control electronic unit in a system. The leakage of EM fields, which couples to internal cables and appear as the induced current and voltage signals. The in-band and out of band noise signals reaches the sensitive circuits and cause the system failure if the level of these signals exceed beyond the upset or damage thresholds. If these noise signals are generated intentionally to disrupt the function of a system, this has opened a new threat in recent years as an Intentional Electromagnetic Interference (IEMI). In this short paper a typical case history of a critical electronic circuit affected by the radiated electromagnetic field from a Walkie-Talkie operating in near vicinity. The retrofit EMI solutions incorporated to reduce the susceptibility of the system are discussed in brief.