“…The output power [7, 17] of the MZM can be expressed as where “ α ” is the fraction of insertion loss of the modulator, “ V π ” is the half-wave voltage, “ V B ” is the bias voltage, “ P 0 ” is the input optical power, “ v in ( t )” is the input RF voltage to the modulator and, “ η ” determines the extinction ratio of the modulator. Therefore, the output voltage of the photo detector when the output of the MZ modulator shines on it is where “ ρ ” is the sensitivity, “ Z ph = R − ( j /ω C )” is the output impedance of the photo-detector and “τ 1 = RC ” is the time-constant of photo-detector.…”