Frequency stabilization of an extended-cavity semiconductor laser by molecule saturation absorption frequency stabilization and self-adapted control

Frequency stabilization of laser diodes is of vital importance for the exploitation of optical frequency-division multiplexing coherent transmission systems and high-resolution optical measurement application. The research of frequency standard in 1.5 mu m region becomes one of hot orientations in optical communication area. The molecules absorption frequency stabilization technology of Fibre Bragg Grating external cavity laser diode (FBG ECLD) is studied intensively. To overcome the shortcoming of traditional PID control, self-organized and self-adapted algorithm based on predictive estimate modelling is used. The algorithm adopts indirectness arithmetic, which estimates and improves on the modelling according to a suitable learning speed and gains perfect control effects. The algorithm which is adopted in embedded system can achieve high-resolution frequency stabilization within 5min warm-up without manual work.