How to balance shielding and heat dissipation of the ventilation openings of a smart controller PAC?

To balance shielding and heat dissipation of the PAC (Power Acoustic Control Unit) ventilation port, waveguide ventilation boards or metal honeycomb panels are required. Waveguide ventilation boards consist of numerous hexagonal waveguide holes with a diameter less than λ/20 (e.g., less than 15mm at 1GHz) and a depth greater than three times the hole diameter, providing a shielding effectiveness greater than 40dB at 1GHz. Metal honeycomb panels offer even higher shielding effectiveness but have greater air resistance. Aluminum alloy is chosen as the ventilation board material, with a conductive anodized surface.

During installation, conductive gaskets are used between the ventilation board and the housing to ensure continuous contact. Simultaneously, the ventilation area is calculated based on heat dissipation requirements to ensure the temperature rise remains within acceptable limits (e.g., less than 20°C). Actual measurements show that using waveguide ventilation boards provides a shielding effectiveness greater than 35dB at 1GHz while meeting heat dissipation requirements, allowing the system to operate continuously at an ambient temperature of 40°C.