A Resonator-Based Suppressor for Mitigating the Noise Transfer on Metal Plates for Control of Electromagnetic Interference

This letter introduces a novel resonator-based suppressor to mitigate the noise transfer on the metal plates inside electronic devices. Compared with the traditional method using ferrite-based absorbers, which is inadequate to fully eliminate gigahertz (GHz) noise, the proposed solution can achieve a high-level noise rejection within the desired frequency band in GHz range. The unit cell of the suppressor is composed of multiple quarter-wavelength (λ /4) strip resonators. By simply cascading unit cells in series, a higher-order suppressor can be implemented with wider bandwidth and deeper suppression level. In this letter, a third-order example is demonstrated with the center frequency at 2.48 GHz. Its ability to reduce the amount of noise transfer is experimentally verified, where the maximum suppression level is about 20 dB. Lastly, for a complete demonstration of noise mitigation, the near-field intensity on the test board attached with the noise suppressor is measured.