Optical Fiber Communications 4th Edition by Gerd Keiser

Exercise 8

A typical DFB laser has a linewidth 1 MHz v 40 MHz, and with a 1- to 10-m optical jumper cable we have 0.005 v 2. With a 1-mjumper fiber and letting v = f= 10 MHz, use the expression in Prob. 9.7 to show that to achieve an RIN of less than -140 dB/Hz, the average reflectivity per connector should be less than -30 dB.