Fig. 1. NRZ/PAM4 system configuration

Fig. 2. Comparison diagram of BER of PAM4 and NRZ signals

Fig. 3. Full-duplex RoF access system

Fig. 4. 4/16/64QAM-OFDM RoF system

Fig. 5. DWDM-RoF system

Fig. 6. Experimental scheme of transmitting and receiving 16QAM-OFDM optical signals based on PTS technology in optical fiber wireless fusion access network

Fig. 7. Principle block diagram of GFDM and comparison diagram of out of band leakage

Fig. 8. Principle of FBMC/OQAM and comparison diagram of side lobe attenuation

Fig. 9. Principle block diagram of UFMC and comparison diagram of power spectral density