- 2 Single Mode Fiber Attenuation And Photodiode Responsivity Consider A Typical Silica Single Mode Step Index Fiber Wit 1 (59.9 KiB) Viewed 36 times
don't skip step
2. Single mode fiber, attenuation and photodiode responsivity Consider a typical silica single mode step-index fiber with a core diameter of 8.2 um operating at 1550 nm with a numerical aperture of 0.12. It is planned for use in a private optical link that stretches 300 km from Toronto to Kingston. Assume a straight link and make necessary good assumptions to find the following: (a) Find the time it takes (the group delay) for an input optical signal to travel from Toronto to Kingston. (b) Find the total attenuation of the optical signal over this length of fiber, neglecting macrobending and connector losses (c) A laser diode is used to launch an optical signal of power 23 dBm into the fiber in Toronto. There are two inline EDFAs (erbium doped fiber amplifiers). Each EDFA provides a gain of 26 dB. What is a typical photocurrent that will be generated by an InGaAs pin photodiode at the Kingston receiving end? If the minimum optical power needed by the photodiode is –30 dBm, how much loss margin do you have?