All optical multi-wavelength single-sideband modulated WDM radio-over-fiber systems by introducing a Sagnac loop filter

All optical multi-wavelength single-sideband modulated WDM radio-over-fiber system by introducing a homemade Sagnac loop filter is proposed and analyzed. The process of the Sagnac loop filter improves the link performance by balancing optical carrier-to-sideband ratio (OCSR). Numerical analysis and simulations are carried out to verify the theory. It is found that the receiver sensitivity is improved by 2.16 dB with OCSR reducing from 4.40 dB to 1.13 dB. In theory, the optimal value of the OCSR can also be achieved. Besides, periodic fluctuation of the RF power is mitigated.