如前所述,利用单位增益段这一概念来设计电缆电视系统。 考虑图2.59所示电缆电视系统的一条干线。注意,全部放大器具有同一输入电平和同一输出电平,因为电缆段的损耗相同。这产生具有单位增益的电缆放大器段,它是干线的构成单元。以前的例子只说明CATV的干线系统。干线电缆是把信 As mentioned earlier, the concept of unity gain section is used to design cable television systems. Consider a trunk of the cable television system shown in Figure 2.59. Note that all amplifiers have the same input level and the same output level because the losses in the cable segments are the same. This results in a cable amplifier section with a unity gain, which is the building block of the trunk. The previous example only shows the CATV trunk system. Trunk cable is the letter