Numerical Analysis of Modal Noise in Optical Waveguides
نویسنده
چکیده
Using the semi-analytic transmission and propagation matrices for guided optical waves, the modal noise in optical waveguide is investigated for a simple three-slab waveguide and a step-index singlemode fiber. It is shown that modal noise can arise from the unbound radation modes which have been excited in the first junction and haven’t been sufficiently attenuated before reaching the second junction. Consequently, ensuring singlemode is not enough even if all cladding modes are also suppressed. It is suggested that all the radiation modes should be also suppressed to eliminate the modal noise and its detrimental effect on the optical networks. The modal noise due to guided modes is, however, severe than that mediated by radiation modes. Key-Words: Modal Noise, Modal Interference, Fiber Splicing, Waveguide Discontinuity
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