High speed free-space optical communication using standard fiber communication component without optical amplification

TL;DR

This paper demonstrates a portable, high-speed free-space optical communication system achieving 9.16 Gbps over 1 km without optical amplification, using standard fiber components and advanced tracking, suitable for field deployment.

Contribution

Developed a miniaturized FSO system with standard fiber components achieving high data rates without optical amplification, and implemented a precise tracking system for reliable free-space links.

Findings

Achieved 9.16 Gbps data rate over 1 km free-space link

Maintained tracking error within 3 μrad

Demonstrated potential for longer distances under better weather

Abstract

Free-space optical communication (FSO) can achieve fast, secure and license-free communication without need for physical cables, making it a cost-effective, energy-efficient and flexible solution when the fiber connection is unavailable. To establish FSO connection on-demand, it is essential to build portable FSO devices with compact structure and light weight. Here, we develop a miniaturized FSO system and realize 9.16 Gbps FSO between two nodes that is 1 km apart, using a commercial single-mode-fiber-coupled optical transceiver module without optical amplification. Using our 4-stage acquisition, pointing and tracking (APT) systems, the tracking error is within 3 {\mu}rad and results an average link loss of 13.7 dB, which is the key for this high-bandwidth FSO demonstration without optical amplification. Our FSO link has been tested up to 4 km, with link loss of 18 dB that is limited by the foggy weather during the test. Longer FSO distances can be expected with better weather condition and optical amplification. With single FSO device weight of only 9.5 kg, this result arouses massive applications of field-deployable high-speed wireless communication.