A 160 Gbps free-space optics transmission enabled by DP-256-QAM and DSP algorithms

Polarization division multiplexing has emerged as an efficient solution for providing high-capacity information transmission rates in optical fiber communication links. But the practical deployment of optical fiber cables is not feasible in many circumstances such as areas having rough terrains and low populated areas keeping in mind the cost-effectiveness. Thus, free-space optics (FSO) transmission provides an effective technological solution in these circumstances and is a viable technology for last-mile broadband access. But, the degradation of optical beam quality in FSO links due to fog environment is a great matter of concern since both the optical beam and the fog particles are similar in size. In this work, we have discussed the simulative modeling and numerical investigation of a 160 Gbps data rate FSO transmission enabled by dual-polarization-256 level-quadrature amplitude modulation (DP-256-QAM) signal under the influence of fog environment. For improving the transmission performance under fog environment, digital signal processing (DSP) algorithms are implemented at the receiver. For analyzing the DP-256-QAM-FSO transmission, bit-error rate (BER) and constellation of the received signals are evaluated. The transmission investigation results exhibit reliable 160 Gbps data transportation at 5.5 km for sunny weather and 730 m for heavy fog environment.