Should edge computing boxes use single-point grounding or multi-point grounding?

The grounding strategy for edge computing boxes needs to be segmented by frequency. Low-frequency circuits (<1MHz) use single-point grounding to avoid ground loop interference. High-frequency circuits (>10MHz) require multi-point grounding to reduce ground wire inductance. Edge boxes handle mixed signal processing, therefore a hybrid grounding is used. Analog and digital grounds are connected at a single point through a 0Ω ferrite bead. The recommended designation is PBZ1608E600Z0T. Its naming convention is PB ferrite bead, Z standard 1608 size, 1.6×0.8mm, E600 impedance, 60Ω, Z tolerance, 0 internal code, T packaging. DC conduction, RF isolation, chassis ground (PE) and signal ground are connected through a 1nF 2kV high-voltage capacitor. AC floating ground is used, while high-frequency noise is coupled to the chassis PCB inner layer ground plane at multiple points. Continuous and dense vias ensure a short return path. For Gigabit Ethernet ports, the CMZ2012A-900T common-mode inductor is used. Its naming convention is CM common-mode Z impedance, 2012 size, 2.0×1.2mm, 900T impedance, 90Ω. The center tap of the 100MHz isolation transformer is connected to signal ground via a 1kV capacitor. This hybrid grounding edge box provides optimal EMC performance with flat ground impedance in the 10kHz-100MHz frequency band.