The merging of optical communication and wireless communication is a tendency in the development of future communication. Orthogonal Frequency Division Multiplexing (OFDM ) technology is becoming a core technology in the physical layer of next generation wireless communication system. Taking advantages of both wireless communication and optical communication, OFDM Radio over Fiber (OFDM-RoF ) system is characterized by high speed, large capacity and high spectral efficiency. However, it still has some problems to be addressed, including dispersion and nonlinearity effects. The nonlinearity effect of fiber and modulator can be mitigated by PAPR reduction algorithms, the dispersion effect can be eliminated using Cyclic Prefix (CP ) and channel estimation, and the fiber nonlinearity can be reduced by techniques such as digital phase conjugation, Partial Carrier Filling (PCF ), nonlinearity precompensation and serial correlation reduction.