Data Communications Networking Devices - 4th Ed.pdf

492 _________________________________ WIDE AREA NETWORK TRANSMISSION EQUIPMENTFigure 4.73Current and emerging cable TV wiring infrastructureto boost signal power since signal loss occurs due to cable distance as well as fromthe splitters encountered in the signal path.The original bandwidth used on CATV systems ranged from 10 to 550 MHz,using 6 MHz per TV channel. Multiple signals are placed on a coaxial cablethrough the use of frequency division multiplexing equipment at the headend, witha tuner in subscriber set-top boxes used to extract the appropriate channel. Thiscabling and multiplexing scheme resulted in most CATV systems providing up to83 channels to subscribers. The entire cable infrastructure of most pre-1995 CATVsystems was based upon the use of coaxial cable as illustrated in Figure 4.73a).The CATV industry has had its share of trials to test different types of cablingand the support of two-way transmission by several competing techniques. One