How to control EMI in concentrator wireless communication?

The concentrator's wireless communication modules (such as 4G and Wi-Fi) are both sources and targets of interference, requiring strict EMI control. For radiation generated by the module itself, select modules with complete shielding and add a π-type filter (PBZ1608E600Z0T ferrite bead + capacitor) at the module's power input. Use shielded cable for the antenna feed and keep it away from digital circuits and power lines. To mitigate the impact of external interference on reception, ensure the antenna is installed away from internal noise sources (such as switching power supplies) of the concentrator; if necessary, use an extension cable to bring the antenna outside the chassis. In software, the wireless module operates at off-peak times compared to high-power transmission periods such as carrier waves. On the PCB layout, the wireless module area is completely surrounded by a ground plane and isolated from other areas by shielded walls. Test and adjust the antenna matching circuit to ensure antenna resonance at the operating frequency, reducing harmonic radiation. Through control, the wireless module's radiated emissions meet FCC/CE standards, while the receiving sensitivity is unaffected by internal noise.