Differential Mode Delay — Full-wave Modelling and Various Levels of Approximations
نویسندگان
چکیده
Differential mode delay (DMD) modelling and measurements provide a means to characterise the modal structure of graded-index multimode fibres. In order to compute DMD output time pulses, we need to solve the modal propagation coefficients, modal group velocities and modal chromatic dispersion, compute the weighted modal amplitudes which are dependent on the excitation, and construct time pulses after propagating a specified distance in the fibre. Based on the measurement specifications in the DMD standard [1], we present a robust full-wave numerical approach and discuss various approximations in the modelling of differential mode delay.
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