A Bidirectional Wireless-Over-Fiber Transport System

This study proposes and demonstrates a bidirectional wireless-over-fiber (WoF) transport system based on an optical interleaver, a phase modulator, and an optical bandpass filter (OBPF)-based phase-modulation-to-intensity-modulation converter that can deliver intensity-modulated 60 GHz millimeter-wave (MMW), 30 GHz microwave (MW), and phase-remodulated 15 GHz MW data signals. A broadband light source, comprising an optoelectronic oscillator scheme and an optical signal-to-noise ratio (OSNR) enhancement scheme, is deployed in these bidirectional 60 GHz/30 GHz/15 GHz WoF transport systems. For downlink transmission, light is promoted optically from a 5 Gbps/ 15 GHz MW data signal to 5 Gbps/60 GHz MMW and 5 Gbps/30 GHz MW data signals in fiber-wireless convergence. The downstream light is phase remodulated successfully using a 5 Gbps/15 GHz MW data signal for uplink transmission. Through a thorough examination of such bidirectional 60 GHz/30 GHz/15 GHz WoF transport systems, the bit error rate (BER) is observed to perform well over a 40 km single-mode fiber and a 4 m RF wireless transmission. This bidirectional 60 GHz/30 GHz/15 GHz WoF transport system is a prominent alternative not only because of its advancement in integrating optical fiber and RF wireless networks but because of the benefits of communication links for broader bandwidth and higher transmission rate as well.