Coherent fiber-optic microcellular radio communication system using RF-to-optic direct conversion scheme

This paper proposes a new coherent fiber-optic microcellular radio communication system using an RF-to-optic direct conversion scheme. In this system a radio signal is converted into an optical signal with the same signaling or multiplexing format for coherent transmission through a wideband optical fiber without any baseband demodulation and modulation. The theoretical analysis and computer simulation of the transmission performance of the radio QPSK and QAM signals clarify that the proposed system improves the optical receiver sensitivity by 4.5 dB compared with conventional coherent analog optical links.