STABLE MICROWAVE GENERATION BASED ON A BRILLOUIN FIBER LASER WITH SATURABLE ABSORBER

摘要

A simple approach to generate stable microwave signals by heterodyning pump light and Stokes lasing light from a dual wavelength Brillouin fiber laser is proposed and demonstrated. A 10-km-long single mode fiber is used as the Brillouin gain medium, and an ultranarrow linewidth distributed feedback laser is used as Brillouin pump, while a 4-m-long unpumped polarization maintaining erbium-doped fiber and subring cavity suppress unwanted side modes. A 10.7 GHz microwave signal is detected by photodetector and the signal linewidth is about 300 kHz. Signal to noise ratio of the microwave signal is about 50 dB. The power and frequency of microwave signal is highly stable, with almost no fluctuations over the test period.