How effective are shielded enclosures for data center switches in suppressing recurrence intervals (REs)?

Fully shielded enclosures for data center switches can reduce radiated emissions by 25-45 dB, making it the most effective means of RE suppression. A typical unshielded prototype has a radiated field strength of 60-70 dBμV/m. Adding a galvanized steel enclosure (1.2 mm thick) reduces this to 35-45 dBμV/m, a reduction of 20-25 dB. Adding conductive foam and springs to ensure continuous seams further reduces the field strength to 25-30 dBμV/m, a cumulative reduction of 30-40 dB. Using copper alloy finger springs (contact resistance <2 mΩ) provides 6-8 dB higher high-frequency shielding effectiveness at 1 GHz than conductive foam. Actual measurements show that with a shielded enclosure and audio interface filtering, the overall RE exceeds the Class B limit margin by >8 dB. The enclosure costs approximately 15-25 RMB more, making it significantly more cost-effective than PCB-level modifications.