Based on the structure of coaxial cables, there are single-layer shielding, double-layer shielding, triple-layer shielding, and solid-state shielding.
Single-layer shielding consists of a single braided layer, covering 70%~90% of the surface, with a shielding effectiveness of -50dB. Corresponding cable models are RG58, RG316, and the national standard SYV-50-7. This type of cable is commonly used in applications below 1GHz.
Double-layer shielding consists of two braided layers, with a shielding effectiveness of -75dB~-85dB, typically reaching 6GHz. Corresponding cable models are RG223, RG142, and RG214.
Triple-layer shielding consists of two braided shielding layers with a foil shielding layer in between, or the first layer is a wound copper tape. The shielding effectiveness reaches -90~-100dB. It is used in EMC testing and microwave cables.
There is also a double-layer shielding structure with a wound + braided structure.
Solid-state shielding is made of a single aluminum or copper tube, with 100% coverage. The shielding effectiveness is -120dB.
