Electromagnetic Propagation in Multimode Optical Fibers, Excited by Sources of Finite Bandwidth.
Abstract
The dependence of the temporal width of the impulse response on the length z of a two-mode optical fiber is examined. This quantity, which is proportional to z in the absence of mode coupling and to z in the presence of weak random coupling among the guided modes, possesses a different dependence in the case of a deterministic resonant-coupling model, appropriate for describing a rather general class of actual situations. The relevant role played by the coherence time of the signal is demonstrated. The effect of strong mode coupling on modal dispersion in optical fibers has been investigated. A coupled system of equations governing the propagation of a signal in a statistical ensemble of multimode optical fibers is presented. The propagation in a multimode optical fiber of a finite bandwidth optical carrier modulated by a nonstationary signal is investigated. The fluctuations of the field due to random modecoupling are considered and the set of coupled equations describing their evolution is derived. In particular, this allows us to investigate the propagation of a frequency-modulated signal and to obtain a general theorem concerning the asymptotic behavior of mode-power fluctuations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 15, 1980
- Accession Number
- ADA088528
Entities
People
- C. H. Papas
Organizations
- California Institute of Technology