FSO performance analysis of a metro city in different atmospheric conditions

In this article, a free-space-optics (FSO) model for a metro city based on real-time visibility data under different weather conditions is presented. Here, the relation between atmospheric attenuation and visibility value and its impact on the FSO performance is carried out. Also, the hybrid-SIM modulation technique is applied for the bit error rate (BER) improvement of the system. Here, Bhubaneswar (the capital of Odisha, India) is considered for the above analysis. The total attenuation, BER, and link margin are calculated for the FSO performance evaluation of Bhubaneswar city and these are simulated using Matlab. The simulation results show that the proposed hybrid-SIM modulation technique achieves about 2.9 dB of SNR improvement than the existing BPSK-SIM technique. Also, from the link margin analysis, it is observed that the sunny day is the most suitable for FSO link transmission. These results can be helpful to decide the FSO parameters and the FSO setup can be designed for any city.

Internet Connectivity: Is Free Space Optics the Solution?

During the Coronavirus disease 2019 pandemic era, poor internet availability hampered online activity, particularly in the sector of education in Malaysia. The most effective way to address this situation is through the construction of telecommunications towers. However, it takes time due to the significant costs involved. Outdoor use of FSO appears to be more advantageous due to the absence of licensing requirements and the high bandwidth it offers. However, there are limitations. We will explore these FSO restrictions in this paper.

Performance Evaluation of a 4 × 20-Gbps OFDM-Based FSO Link Incorporating Hybrid W-MDM Techniques

Free space optics (FSO) has been recognized as a crucial technique to meet the high-bandwidth requirements in future wireless information transmission links. It provides a feasible solution to the last-mile bottleneck problem due to its merits that include high-speed data transportation and secure and low-latency networks. Due to these merits, FSO is a reliable technology for future health-care and biomedical services like the transmission of biomedical sensor signals. But the main limiting factor in the data transmission employing FSO links is adverse atmospheric weather conditions. This research work reports the designing and simulative evaluation of the performance of a high-speed orthogonal frequency division multiplexing–based free space optics link by incorporating wavelength division multiplexing of two independent frequency channels (193.1 THz and 193.2 THz) along with mode division multiplexing of distinct spatial laser Hermite–Gaussian modes (HG01 and HG03). Four independent 20-Gbps quadrature amplitude-modulated data signals are transported simultaneously under different atmospheric weather conditions using the proposed link. Also, the link performance has been investigated for an increasing beam divergence angle.