A coaxial cable is a type of transmission line composed of inner and outer conductors separated by an insulating layer. Its core structure features a coaxial arrangement: the inner conductor (typically a solid core or stranded wire) is encased in a dielectric insulator, while the outer layer consists of a shielding layer-formed by a metal braid or metal foil-and is protected by an outermost jacket.
Technical Principles and Structural Advantages
Coaxial cables rely on the transmission of electromagnetic waves between the inner and outer conductors; the shielding layer serves to block external electromagnetic interference, thereby ensuring signal integrity. The cable exhibits stable impedance characteristics, with common specifications being 50Ω (typically used for RF transmission) and 75Ω (typically used for video signals). The inner conductor material varies; copper-clad aluminum cores, for instance, strike a balance between conductivity and cost-effectiveness, making them suitable for medium-to-long-distance transmission. Furthermore, the cable's circular cross-section helps to minimize signal attenuation. The shielding layer, constructed from metal braiding or aluminum foil, achieves shielding efficiencies exceeding 90%, thereby effectively suppressing wireless interference.
