Lightning protection of microwave radio equipment using radio on fiber and power over fiber experimental demonstration of communication quality

It is known that lightning causes damage to microwave radio equipments used by electric power industry in Japan. We have proposed a system configuration using optical fiber cables instead of metal waveguides in order to protect microwave radio equipment from lightning. In this paper, an experimental demonstration using transmitting radio on fiber (RoF) link and receiving RoF link is introduced and measured total communication characteristics are also reported. In the experiments, antenna side optical to electrical (O/E) and electric to optical (E/O) converters were worked by power over fibers. We have successfully confirmed more than 37dB carrier-to-noise ratio (CNR) under the 26dB dynamic range of received signal strength of 6.74GHz, 64QAM (quadrature amplitude modulation), 37.5Mbps radio frequency (RF) signal. This result shows the proposed configuration can perform applicable communication quality.