Nonlinear distortion performance of semiconductor laser diodes influenced by coherent reflected waves

The influence of the coherent reflected waves on the non-linear distortion performance of semiconductor laser diodes excited by an arbitrary number of input sinusoids with arbitrary amplitudes is analyzed by using the modified simple nonlinear rate equations. The special case of relatively small input amplitudes is considered, and closed-form expressions for the amplitudes of the resulting harmonics and intermodulation products of any order, as well as the differential gain, are obtained.