Coaxial cables can be divided into baseband coaxial cables and broadband coaxial cables (ie, network coaxial cables and video coaxial cables). Coaxial cable is divided into 50Ω baseband cable and 75Ω wideband cable. The baseband cable is divided into a thin coaxial cable and a thick coaxial cable. The baseband cable is only used for digital transmission with a data rate of up to 10Mbps.
Coaxial cable refers to a cable that has two concentric conductors, and the conductor and shield share the same axis. The most common coaxial cable consists of a copper conductor isolated from an insulating material. On the outside of the inner insulation is another layer of ring conductor and its insulator. The entire cable is then covered by a sheath of polyvinyl chloride or Teflon.