Amplifier

When telephone conversations travel through a medium, such as a copper wire, they encounter resistance and thus become weaker and more difficult to hear. An amplifier is an electrical device which strengthens the signal. Unfortunately, amplifiers in analog circuits also strengthen noise and other extraneous garbage on the line. Cascading amplifiers, therefore, compound, or accumulate, noise. Digital systems make use of regenerative repeaters, which regenerate (i.e. reshape or reconstruct) the signal before amplifying it and sending it on its way. As a result, noise is much less prevalent and less likely to be amplified in digital systems, whether one or many repeaters are in place. The ultimate yield of a repeater in a digital environment is that of improved error performance, which also yields improved throughput, assuming that error correction involves retransmission.