(a) A step-index fiber has a core diameter of 12-μm. The core refractive index is 1.445 and a relative refractive index difference Δ of 0.2% at operating wavelength 1.3-μm. i.How much is the velocity of light within the core of this fiber? ii.How many modes can this fiber support? iii.Determine the condition of the relative refractive index difference Δ to make the fiber operate in the single mode at operating wavelength 1.2-μm. (b) A step-index multi-mode fiber has a length of 2.3 km, core index n1=1.45, Δ=0.01, (i) please calculate the modal delay in this optical fiber. (ii) Please estimate the limit of bit-rate distance product of this fiber.

(a) A step-index fiber has a core diameter of 12-μm. The core refractive index is 1.445 and a relative refractive index difference Δ of 0.2% at operating wavelength 1.3-μm. i.How much is the velocity of light within the core of this fiber? ii.How many modes can this fiber support? iii.Determine the condition of the relative refractive index difference Δ to make the fiber operate in the single mode at operating wavelength 1.2-μm. (b) A step-index multi-mode fiber has a length of 2.3 km, core index n1=1.45, Δ=0.01, (i) please calculate the modal delay in this optical fiber. (ii) Please estimate the limit of bit-rate distance product of this fiber.