Transparent Microwave Photonic Filter Based on Brillouin Losses in Optical Fiber

Cheng Feng; Stefan Preussler; Thomas Schneider

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arXiv · 1709.07055

Transparent Microwave Photonic Filter Based on Brillouin Losses in Optical Fiber

Cheng Feng·Stefan Preussler·Thomas Schneider

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Abstract

In this paper, we propose a low-noise, bandwidth tunable microwave photonics filter (MPF) based on stimulated Brillouin scattering (SBS) losses. By suppressing the out-of-band signal with two broadened symmetric SBS losses, pass bandwidth can be tuned from 500 MHz to 10 GHz. Considering the limited interaction in the center frequency range, a flat-top response with 0.3 dB ripple is easily achieved. Unlike a SBS gain based filter, due to the transparency of the pass band in our proposed filter, hardly no noise is detected in a noise measurement against an obvious maximum 5 dB noise pedestal for a SBS gain based one. Considering the wide independent bandwidth and center frequency tunability, flat-top response, and low-noise characteristic, our proposed filter can be perfectly used as a supplement of most commericalized tunable single bandpass filters, whose minimum bandwidth is limited by 10 GHz.

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Cheng Feng, Stefan Preussler, Thomas Schneider. 2017-08-02. Transparent Microwave Photonic Filter Based on Brillouin Losses in Optical Fiber. https://arxiv.org/abs/1709.07055

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