In communication devices like base stations, the cavity of the cavity filter is made of aluminum alloy through CNC milling. CNC machining precisely controls the size and internal structure, for example, controlling the inner wall roughness of the cavity within Ra0.8 - Ra1.6μm to guarantee performance and enhance the filtering effect. For the ceramic dielectric resonator of the dielectric filter, with the precision grinding and cutting processes of CNC, its dimensional accuracy is controlled within ±0.05mm to meet high - frequency performance requirements and ensure the stability of the resonant frequency.

RF coaxial connectors are used to connect RF cables and communication devices, and the inner and outer conductors of their plugs and sockets require high-precision machining. CNC machines process metal materials into precise sizes and shapes through turning and milling to ensure the electrical and mechanical properties of the connectors. For example, the diameter tolerance of the inner conductor is controlled within ±0.02mm and the roundness of the outer conductor within ±0.01mm to ensure impedance matching and signal transmission quality. Connectors in the microwave and millimeter-wave bands have more stringent precision requirements. CNC uses processes such as precision grinding and electrical discharge machining to produce connector components with nanometer-level precision. For instance, electrical discharge machining can create tiny bumps and grooves on the connector's contact surface, increasing the contact area, reducing the resistance, and improving the high-frequency performance of the connector.

As the carrier of electronic components in communication devices, the manufacturing of PCB relies on CNC machining technology. Through processes such as drilling, milling and etching, CNC can precisely create circuit patterns and mounting holes on the insulating substrate. Drilling can control the hole diameter accuracy within ±0.05mm to ensure the accurate installation of components, and milling is used to process the shape of PCB to fit the size of the device. Multilayer circuit boards are widely used in the communication field, and their manufacturing is complex. CNC needs to accurately control the thickness and alignment accuracy of each layer of the board. Through the lamination and positioning processes, the thickness tolerance and interlayer alignment accuracy are respectively controlled within ±0.05mm to ensure the signal transmission quality between layers.