Analysis of multimode fiber bandpass characteristics using Gaussian distributed delays

Multimode fiber is one of two major types of optical fibers used in practice. Its capacity in terms of the available bandwidth for signal transmission can be increased significantly if the signal is transmitted over the passbands at high frequency range. However, it has been shown that as the frequency increases, the magnitude response of multimode fibers is reduced and becomes relatively flat at a particular level. It has also been shown that such phenomenon is the consequence of having many guided modes reaching the receiving end with different time delays. In this paper, the characteristics of such passbands of multimode fibers are analyzed theoretically. The guided mode delays are assumed to be Gaussian distributed. The average magnitude response of multimode fiber at high frequency range and the average bandpass bandwidth are studied. The obtained results are useful in the signal transmission over multimode fiber in order to make use of the available passbands effectively.