부산대학교 도서관

A new concept of a radio-over-fiber (RoF) system, namely, “delta-sigma RoF embedding a pulse-distortion model (PDM),” for beyond fifth-generation mobile-communication systems is proposed. The PDM is generated by a distorted baseband feedback signal. To implement the proposed concept, an all-digital transmitter based on modified low-pass delta-sigma modulation, a simple PDM in the RoF channel, and a method for optimizing the parameters of the model are also proposed. An experimental demonstration using a l-GHz-bandwidth OFDM signal showed that the proposed delta-sigma RoF system improved in-band signal-to-noise ratio (SNR) by 6 dB compared to that of a conventional delta-sigma RoF system and achieved in-band SNR of 30.7 dB after 23.6-Gbps fiber transmission.