Transmission Characteristics of Graded-Index Multimode Fibers


IEICE TRANSACTIONS (1976-1990)   Vol.E61    No.3    pp.209-212
Publication Date: 1978/03/25
Online ISSN: 
Print ISSN: 0000-0000
Type of Manuscript: Special Section PAPER (Special Issue on Integrated Optics and Optical Fiber Communications)

Full Text: PDF>>
Buy this Article

From theoretical or experimental point of view, graded-index multimode fibers are interesting and promissing transmission lines for future optical communication systems. Their transmission characteristics, however, have not been well recognized so far. Therefore, it is necessary to clarify the characteristics before considering graded-index multimode fibers for practical uses. Among the characteristics, optical loss and pulse dispersion are of paramount importance. This paper presents baseband frequency characteristics of recently produced graded-index multimode fibers in the frequency range from DC to 1.7 GHz. The characteristic dependence of graded-index multimode fibers on wavelength and excitation condition is also studied in comparison with that of a step-index multimode fiber. Wavelength, rather than excitation condition, is shown to be an important factor that determines the characteristics of the fiber. The wavelength dependence of the bandwidth has been found to be critically influenced by the profile of the fiber. In order to understand the detailed characteristics of graded-index multimode fibers, the measurement covering a wide frequency range, e. g., from DC to over 2 GHz, is necessary.