ABSTRACT
Frequency modulation of laser diodes is a key component in Phase-Generated Carrier (PGC) systems which use Michelson interferometers. The value of C is an important parameter in measuring the frequency-modulation properties of laser diodes and plays an important role in PGC demodulation expression. The original expression of C depends on the largest frequency shift and arm difference between the two arms of the Michelson interferometer. However, according to our analysis, the value of C also depends on modulation frequency. With an increase in modulation frequency, the value of C will decrease, indicating that the modulation efficiency also decreases.
