Performance trade-off of coaxial and fiberoptic cables

In this paper coaxial and fiberoptic cables are traded off by comparing maximum length over which a signal can be transmitted as a function of bandwidth. The calculations verify that coax bandwidth decreases much more rapidly than that of fibers, for unrepeatered length. More specifically, at low and high frequencies, coax bandwidth decreases as 1/L² while optical fiber bandwidth, in the absence of mode mixing, varies at most as 1/L. Curves of unrepeatered length as a function of bandwidth for both coax and fiber are presented under a variety of operating regimes.