Fig. 1. Conceptual diagram of the proposed frequency-tunable RoF system.

Fig. 2. (a) Illustration of the operation of the MPF and (b) the MPF frequency response.

Fig. 3. Schematic of the wideband frequency-tunable MPF. PC, polarization controller; OC, optical coupler.

Fig. 4. (Color online) Superimposed frequency responses of the MPF.

Fig. 5. Experimental diagram of the proposed frequency-tunable RoF system.

Fig. 6. (a) Reflected and (b) transmitted spectrum of the PS-FBG.

Fig. 7. (Color online) Generated microwave signals with different frequencies.

Fig. 8. Spectrum of the generated RF signals at PD2.

Fig. 9. Spectrum of the received baseband signals: (a) BTB with the received optical power of 2 dBm, (b) 10 km with the received optical power of 0 dBm.

Fig. 10. BER curves and the eye diagrams of the signals at different transmission distances BTB and 10 km.