What is Coaxial Cable ?
A coaxial cable is an electrical cable with a copper conductor and an insulator shielding around it and a braided metal mesh that prevents signal interference and cross talk. Coaxial cable is also known as coax.
The core copper conductor is used for the transmission of signals and the insulator is used to provide insulation to the copper conductor and the insulator is surrounded by a braided metal conductor which helps to prevent the interference of electrical signals and prevent cross talk. This entire setup is again covered with a protective plastic layer to provide extra safety to the cable.
Structure of Coaxial Cable
Copper conductor: A central conductor, which consists of copper. The conductor is the point at which data transmits.
Insulator: Dielectric plastic insulation around the copper conductor. it is used to maintain the spacing between the center conductor and shield.
Braided mesh: A braided mesh of copper helps to shield from electromagnetic interference, The braid provides a barrier against EMI moving into and out of the coaxial cable.
Protective plastic layer: An external polymer layer, which has a plastic coating. It is used to protect internal layers from damages.
Types of Coaxial cables
- Hardline coaxial cable: Hardline coaxial cable’s center conductor is made of copper, silver and has a larger diameter when compared to other coaxial cables.
- Flexible coaxial cable: The flexible coaxial cables are very flexible and the inner conductor is surrounded by a flexible polymer.
- Semi-rigid coaxial cable: Semi-rigid coaxial cable uses a solid copper outer sheath with a dielectric of Polytetrafluoroethylene.
- Formable coaxial cable: It is an alternative to semi-rigid cable, instead of a rigid copper outer sheath a flexible metal sheath is utilized.
- Twinaxial cable: It has two central conductors in the core and a single outer core and dielectric. these cables are best for low-frequency digital and video transmission.
- Triaxial cable: It is also known as Triax. It is very much similar to a coaxial cable but with an additional copper braid added to it, the braid works as a shield and protects from noise. Triaxial cables offer more bandwidth.
- Rigid coaxial cable: Rigid coaxial cable is made up of two copper tubes supported at cable ends and fixed intervals across the length of the cable using PTFE supports or disk insulators. The rigid coaxial cable cannot be bent. It is mainly used in TV and FM broadcasting systems.
Applications of Coaxial cable
The coaxial cables are used in Ethernet LANs and also used in MANs
- Television: Coaxial cable used for television would be 75 Ohm and RG-6 coaxial cable.
- Internet: Coaxial cables are also used for carrying internet signals, RG-6 cables are used for this.
- CCTV: The coaxial cables are also used in CCTV systems and both RG-59 AND RG-6 cables can be used.
- Video: The coaxial cables are also used in video Transmission the RG-6 is used for better digital signals and RG-59 for lossless transmission of video signals.
- HDTV: The HDTV uses RG-11 as it provides more space for signals to transfer.
- Coaxial cables support high bandwidth.
- It is easy to install coaxial cables.
- coaxial cables have better cut-through resistance so they are more reliable and durable.
- Less affected by noise or cross-talk or electromagnetic inference.
- Coaxial cables support multiple channels
- Coaxial cables are expensive.
- The coaxial cable must be grounded in order to prevent any crosstalk.
- As a Coaxial cable has multiple layers it is very bulky.
- There is a chance of breaking the coaxial cable and attaching a “t-joint” by hackers, this compromises the security of the data.