Fig. 1. Schematic diagram of the proposed OEO.

Fig. 2. Simulated frequency response of (a) the FIR filter, (b) the IIR filter, and (c) the cascade of the FIR and IIR filters. (d) The power spectrum of the oscillating signal of the OEO.

Fig. 3. Simulated electrical spectra at different frequencies. (solid lines: the electrical spectra of the RF signals; dashed line: the frequency response induced by the chromatic dispersion of the DCF).

Fig. 4. Optical spectra of the BOS (a) after the OBPF and (b) after the MZI.

Fig. 5. MPF’s frequency response at different frequency points measured by the VNA.

Fig. 6. Electrical spectra of the 20 GHz oscillating signal (a) with and (b) without the RDL.

Fig. 7. Tuning electrical spectra (a) from 10.3 to 26.7 GHz with a step of 1 GHz and (b) from 18.2 to 19.2 GHz with a step of 100 MHz.

Fig. 8. (a) Frequency fluctuations and (b) Allan variances of the OEO.

Fig. 9. SSB phase noise comparison (a) at different frequency points and (b) with different fiber lengths at 10.3 GHz.