Signal Distortion in Optical Fibers Part 5: Core and Cladding Loss

 
. Since the core and cladding have different indices of refraction hence they have different attenuation coefficients α₁ and α₂ respectively.

. For step index fiber, the loss for a mode order (v,m) is given by,

       For low-order modes, the expression reduced to

. For graded index fiber, loss at radial distance r is expressed as,

       The loss for a given mode is expressed by,

       Where, P(r) is power density of that mode at radial distance r.