Brillouin amplification-a powerful new scheme for microwave photonic communications

Abstract

In this paper we introduce a powerful technique called Brillouin selective sideband amplification (BSSA) to drastically improve the performance and extend the functionality of an analog photonic system. This optical amplification process is much more efficient than any other optical amplification method because all Brillouin scattering energy from the pump laser goes directly into the desired weak sideband, not to the strong optical carrier. Consequently the saturation of the receiving photodetector can also be avoided. We obtained a net link gain of 20 dB of an externally modulated photonic link at 5 GHz with an optical power of only 2.6 mW in the photodetector. Such a large and efficient signal amplification will prove extremely important in systems with narrow instantaneous bandwidth but broad overall bandwidth (e.g. widely tunable systems).