Studying the double Rayleigh backscattering noise effect on fiber-optic radio frequency transfer

We report the effect of the double Rayleigh backscattering (DRB) noise, in which the interference of the signal light with the double Rayleigh backscattered light, on the fiber-optic radio-frequency (RF) transfer system. Here, we theoretically analyze and experimentally demonstrate that the DRB noise within the fiber link will become the dominate noise on the fiber-optic RF transfer system once narrow linewidth lasers are used. The strong DRB noise is experimentally confirmed through the measurement of the effect of the coherent interference term of the signal light and the double Rayleigh backscattered light on the 100 km RF transfer system. Our results provide evidence that the conventional RF transfer technique with the telecommunications-grade lasers, in which the chromatic dispersion effect in the single-mode fiber is compensated by dispersion compensation fibers (DCFs), could be the better choice for high-performance RF transfer.