Essential Guide to Telecommunications, The, Third Edition

Bandwidth—Measuring Capacity

In telecommunications, bandwidth refers to capacity. Bandwidth is expressed differently in analog and digital transmissions. The carrying capacity of analog media, such as coaxial cable, is referred to as hertz. Hertz is a way of measuring the capacity or frequency of analog services. The bandwidth of an analog service is the difference between the highest and lowest frequency within which the medium carries traffic. For example, in the early 1980s when the government gave spectrum (a range of frequencies) rights to local telephone companies for analog cellular service, it gave it to them in the range of 894 MHz to 869 MHz. It gave them 25 megahertz (894 – 869 = 25) of spectrum. The greater the difference between ...