Massively Parallel Free Space Optical Communications Based on Soliton Microcomb

Free space optical (FSO) communication has aroused great interest in both of scientific and engineer communities with the advantages of large communication capacity, high data rate, good security and confidentiality, strong anti-electromagnetic interference ability, light weight, low power consumption and convenience deployment. In this paper, a soliton microcomb (SMC) is used as a multi-wavelength laser source, and the multi-channel spatial data transmission experiment is carried out based on the dense wavelength division multiplexing system. Experiments prove that with a modulation of quadrature phase shift keying at a transmission rate of 5 Gbit/s per channel, the bit error rate is lower than the forward error correction threshold of 7% overhead when the carrier optical signal-to-noise ratio is higher than 23.88 dB, and a total of 60 comb lines of SMC have 300 Gbit/s data transmission capacity on a 100 m spatial transmission link. The proposed free space optical communication system based on SMC has broad application prospects in inter-satellite communication, military applications, disaster recovery and other fields.