Performance analysis of long-distance radio-over-fiber systems for mainland-island communications

For mainland-island communication applications, radio-over-fiber (RoF) links which have been commonly designated for short-reach access networks need to be re-designed due to the long geogrgphical distance nature. In this paper, we present a calculating model of long-distance RoF communication systems that connect mainland and islands using intensity modulation (IM) technique, two erbium-doped fiber amplifiers (EDFAs) and coherent receiver for transferring mobile RF signal. Signal and noise powers, signal-to-noise ratio (SNR) and bit-error rate (BER) of these systems are calculated and determined. We then build algorithm chart to find out system's essential parameter values including transmitter power, local oscillator power, EDFA's Gains, EDFA's position on the link so that BER values at the receiver are in the interval of [10
⁻¹⁴
-10
⁻¹⁰
] corresponding to different lengths (200–300) km. Next, we write and make MatLab-based program run to show system performance under the impacts of fiber link length, transmitter's laser power, and receiver's local oscillator. The results could be used effectively in calculating, designing and operating the long-distance RoF systems.