Weather-limited in-band full-duplex transceiver model for free-space optical communication

Abstract

Free-space optical (FSO) communication has gained popularity for wireless applications over legacy radio frequency for advantages such as unlicensed operation, spatial reuse, and security. Even though FSO communication can achieve high bit rates, range limitation due to strong attenuation and weather dependency has always restricted its practical applications to controlled settings such as building-to-building communication. Futuristic mobile and secure ad hoc FSO network applications such as smart cars and air-subsea links need more efficient and autonomous link acquisition capabilities, which can be enabled by in-band full-duplex (IBFD) operation. We proposed an IBFD-FSO transceiver prototype consisting of off-the-shelf components to demonstrate the concept of IBFD operation by the isolation technique. We also developed a laser-based IBFD-FSO link model by incorporating an atmospheric attenuation model and self-interference cancellation model. We found that, for clear weather, the maximum achievable link range using commercially available components can be up to 120 m. We also determined weather-dependent performance of the FSO link in terms of visibility and transmit power.