Communication cables are cables that transmit telephone, telegraph, fax documents, television and radio programs, data and other electrical signals. It is formed by twisting more than one pair of mutually insulated wires. Compared with overhead open wires, communication cables have the advantages of large communication capacity, high transmission stability, good confidentiality, and are less affected by natural conditions and external interference. The cable core is composed of a plurality of mutually insulated wires or conductors, and the communication line is provided with a sealing sheath on the outside. Some are also equipped with an outer sheath outside the sheath. There are various laying methods such as overhead, direct burial, pipeline and underwater. According to the structure, it is divided into symmetrical, coaxial and integrated cables; according to functions, it is divided into field and permanent cables (underground and submarine cables). The communication cable has a wider transmission frequency band, a larger communication capacity, and less external interference, but it is not easy to repair. It can transmit telephone calls, telegrams, data and images, etc.Communication cable (English name: communication cable) refers to the cable used for short-distance audio communication and long-distance high-frequency carrier and digital communication and signal transmission. It is one of the five major cable products in China. According to the purpose and scope of use of communication cables, they can be divided into six series of products, namely local communication cables (including paper insulated local telephone cables, polyolefin insulated polyolefin sheathed local telephone cables), long-distance symmetrical cables (including paper insulated local telephone cables) Insulated high and low frequency long distance symmetrical cable, copper core foam polyethylene high and low frequency long distance symmetrical cable and digital transmission long distance symmetrical cable), coaxial cable (including small coaxial cable, medium coaxial cable and micro coaxial cable), submarine cable (dividable Symmetric submarine and coaxial submarine cables), fiber optic cables (including traditional cable type, ribbon array type and skeleton type), radio frequency cables (including symmetrical radio frequency and coaxial radio frequency).