Design and applications of radio-over-fiber schemes to indoor wireless coverage and highspeed rails

A low-cost radio-over-fiber (RoF) based integrated transmission of long term evolution (LTE) and worldwide interoperability for microwave access (WiMAX) signals is proposed to solve the shadowing effect of building envelopes and the complexity of transmitting system in wireless access network services. This scheme is also applied to solve the problems of required fast handover and poor signal penetration in tunnels for high-speed rail mobile connections. We design and demonstrate experimentally a multi-service WiMAX/LTE RoF system that can extend the indoor signal coverage, with an emphasis on the power conversion efficiency and optoelectronic component selections. The designed RoF transceivers and switches are being deployed in both the campus buildings and the tunnels of Taiwan High-Speed Rail system to allow mobile connections.