Low-Power, Reconfigurable Brillouin RF Photonic Bandstop Filters

Stimulated Brillouin Scattering (SBS) has been widely used to realize narrowband as well as wideband microwave photonic bandstop filters. However, most Brillouin based wide-band bandstop filters require large powers and have high complexity. In this letter, we propose a novel approach to realize a wideband, reconfigurable and tunable Brillouin-based microwave photonic bandstop filter using RF phase engineering. We demonstrate bandstop filters with suppression of >15 dB for moderate bandwidths and maximum bandwidth reconfigurability up to 1 GHz by using two pumps with powers of 8.2 dBm and 9.3 dBm. Further, we also demonstrate switching from a bandpass to a bandstop filter with simple phase manipulations. This letter presents numerical simulations, analysis, and experimental results for the proposed filter. Compared to conventional Brillouin systems, the proposed filter is extremely power-efficient.