An optical fiber is transmitting in the third window (? = 1.55 µm) a signal with bandwidth B = 30…

An optical fiber is transmitting in the third window (λ = 1.55 µm) a signal with bandwidth B = 30 kHz centered at f0 = 10 MHz. The fiber has specific attenuation, delay and dispersion coefficients per unit length respectively of  and  Determine the receive amplifier noise figure to assure a SNR of 20 dB at the system output if the fiber link is 70 km long and the transmitted power is 1 dBm.