2 2.1 A data transmission system uses a 1.5 mW laser diode that operates at a wavelength of 800 nm. The fiber used is a multimode graded index fiber with an attenuation constant of 2.5 dB/km. Every 2 km the fiber is jointed by a fusion splice resulting in an additional 0.5 dB loss per splice. The required optical power at the detector to ensure a bit-error-rate of less than 10-9, is -42 dB. 2.1.1 What is the maximum loss in dB that will still ensure adequate operation of the transmission system? (4) 2.1.2 What is the maximum fiber length in the communication system? (4) 2.1.3 If the laser diode is replaced with a 600 W LED, determine the maximum fiber length