A coaxial cable system for analog signal transmission using cable television is known as a broadband coaxial cable. The word "broadband" from the industry, is the ratio of 4kHz wide band. In computer networks, however, "broadband cable" refers to any cable network that uses analog signals for transmission.
The broadband network using standard cable television technology, can use the frequency band up to 300MHz (often 450MHz); due to the use of analog signal, need an electronic device placed in the interface, in order to enter the network bit stream into an analog signal, and the signal output of the network is converted into a bit stream.
Broadband systems are divided into multiple channels, and television broadcasting usually takes up 6MHz channels. Each channel can be used to simulate television, CD quality, voice (1.4Mb/s) or 3Mb/s digital bit streams. Television and data can be mixed and transmitted over a single cable.
One of the main differences between broadband systems and baseband systems is that broadband systems require periodic amplification of signals due to the wide range of coverage. These amplifiers can only transmit signals in one direction, so if there is an amplifier between the computers, packet packets can not be transmitted back and forth between computers. To solve this problem, two types of broadband systems have been developed: double cable system and single cable system.