Features of coaxial cable

Coaxial cable is a kind of cable dedicated to data and signal transmission, consisting of a center conductor, insulation layer, mesh shield layer, outer insulation layer and sheath layer. The central conductor of the coaxial cable is a metal wire, usually made of copper or aluminum, the insulating layer is usually made of polypropylene or polyethylene, and the mesh shielding layer is covered by the insulating layer and is made of copper wire or aluminum foil. Coaxial cable is widely used in computer networks, TV signal transmission, security systems, radio stations and other fields.

The following are some of the main features of coaxial cable:

 1. Anti-electromagnetic interference: The internal mesh shielding layer of coaxial cable can effectively resist external electromagnetic interference and ensure the stability and reliability of signal transmission.

 2. Large capacity: The central conductor of the coaxial cable is a metal wire, good conductivity, large capacity, can transmit high frequency signals.

 3. Long signal transmission distance: the signal transmission distance of coaxial cable is farther than that of general cable, and the transmission distance is generally ranging from a few kilometers to dozens of kilometers.

 4. Sheath layer protection: coaxial cable outer insulation layer and sheath layer can effectively protect the cable center structure and extend the service life of the cable.

 5. Characteristic impedance: the main component of the coaxial cable is the inner and outer two conductors, the current through the conductor will produce resistance and inductance, and the conductance and capacitance between the conductors will be generated, and distributed along the line, also known as distributed copy.

As a result, the actual characteristic impedance of the coaxial cable will be higher than the theoretical value when connecting the display system. Therefore, in order to avoid the signal capability reflection generated by this situation and ensure the best transmission effect, the terminal load impedance is required to be consistent with the cable characteristic impedance as much as possible.

 6.Attenuation characteristics: The attenuation characteristics of coaxial cable are generally identified by the attenuation constant, which is equivalent to the decibels of the signal attenuation of the current per unit length. The attenuation constant of the coaxial cable is proportional to the operating frequency of the signal, that is, the higher the frequency generated, the greater the attenuation constant, the lower the frequency, the smaller the attenuation constant.

 It should be noted that the types and specifications of coaxial cables vary according to different application scenarios and needs. When choosing a coaxial cable, it is necessary to consider the frequency of the transmitted signal, the transmission distance, the use environment, the interface type and other factors, so as to select the appropriate model and specification