Passive Shielding Integrity Monitoring Method Using Signals-of-Opportunity and Software-Defined Radios

Abstract

Effective shielding is crucial for a range of applications, such as safeguarding information-sensitive systems and providing protection against the effects of high-altitude, nuclear, or lightning-induced electromagnetic pulses. Since the deterioration of the shield can have serious consequences, real-time monitoring is critical to ensure the continuous shielding integrity. Conventional shielding effectiveness measurement techniques are limited to periodic evaluations, making them unsuitable for real-time monitoring. Furthermore, conventional shielding effectiveness measurements rely on high field strength electromagnetic signals which are not desired for continuous assessment. This article proposes a passive shielding integrity monitoring method particularly designed for on-site conditions, using signals-of-opportunity and software-defined radio-based receivers. Unlike conventional methods, due to its small footprint, the proposed method is able to be applied in operational enclosures with contents. Experimental results have shown the feasibility and adaptability of the proposed method. The proposed method allows the bridging between periodic evaluations and real-time monitoring and helps in mitigating the risks associated with the potential electromagnetic leakage of interfering signals or compromising emanations, thereby significantly enhancing information security for sensitive environments and critical infrastructure.