Optical single sideband-frequency generation with carrier totally suppressed for Brillouin distributed fiber sensing

The power fluctuation and multi-sidebands of the RF modulated electro-optic intensity modulator (EOIM) can lead to a degraded resolution of the Brillouin distributed sensors. A standard commercial fiber-pigtailed DFB-LD is locked to one of the sidebands of the EOIM. Optical single sideband-frequency generation is realized with the carrier and the other sidebands totally suppressed. The locked LD greatly improves the power stability of the injected sideband. No dc bias controlling to the EOIM is needed in the locking process. This simple method provides large tuning range (∼1 GHz), fast response (∼100 μs), and high side-frequency suppression ratio (∼60 dB). Thus, it is practical for high-resolution Brillouin sensing systems as well as microwave photonics.