ABSTRACT
Besides the power attenuation by the fiber, the other very important transmission characteristic for telecommunication applications is the signal distortion introduced by the fiber. This chapter considers only linear phenomena; that is, assumes the power level launched into the fiber to be less than the threshold for nonlinear effects. Under these conditions, the only sources of signal distortion are the difference in propagation delay time between the two LP01 modes and the variation of propagation delay time with wavelength. The chapter reviews the effects of both types of dispersion and then discuss the corresponding limitations on the possible bit rates. The term dispersion-free fibers apply to fibers where the second-order dispersion term vanishes, although the third-order term is generally different from zero. Fibers exhibiting a low dispersion over a broad wavelength range are of interest for the purpose of increasing the fiber transmission capacity through wavelength multiplexing.
