Passive Optical Networks

1.1.3 Fiber Access Systems

Local loops using optical fiber for access connections are called fiber-in-the-

loop (FITL) systems [8–9]. Optical fiber has the advantage of high bandwidth,

low loss, and low noise. Compared to the coaxial cable plant, which usually

requires many cascaded RF amplifiers, fiber plants are in general much cleaner

and require very little maintenance.

Studies for FITL started in the 1980s [10–11]. Fiber access systems are also

referred to as fiber-to-the-x (FTTx) system, where ‘‘x’’ can be ‘‘home,’’ ‘‘curb,’’

‘‘premises,’’ ‘‘neighborhood,’’ etc., depending on how deep in the field fiber is

deployed or how close it is to the user. In a fiber-to-the-home (FTTH) system,

fiber is connected all the way from the service provider to ...