60 GHz 5G Radio-Over-Fiber Using UF-OFDM With Optical Heterodyning

Millimeter-wave communications may be harnessed to help meet future 5G network bandwidth requirements, but the generation of these frequencies in the electronic domain can be difficult and costly. Photonic techniques, such as optical heterodyning, can be exploited to generate millimeter-wave frequencies in a manner which is efficient and compatible with fiber transport infrastructure. In this letter, analog radio-over-fiber transmission of five bands of UF-OFDM, with optical heterodyning around 60 GHz, is experimentally demonstrated over 25 km SSMF, and performance well below the forward error correction limit is achieved for an aggregate raw bit rate of 4.56 Gb/s. Additionally, the importance of precise optical phase correlation in these systems is highlighted with respect to future 5G system requirements.