Advanced Optical-Radio Communication System for 5G Base Stations at 60 GHz Using MMW-FSO Links with Integrated Space-Division Multiplexing

This research aims to create trustworthy, fast communication technologies for 5G and beyond. The design investigates the possibilities of Free-Space Optical (FSO) communication systems and MilliMeter-Wave (MMW) technologies operating at 60 [GHz]. Although these technologies are highly effective and have a high throughput, they are nevertheless vulnerable to weather phenomena like rain, fog, and Atmospheric Turbulence (AT). The paper suggests using Space Division Multiplexing (SDM) and the MMW-FSO link to develop optical-radio communication systems. The proposed systems aim to transmit data to four compact 5G Base Stations (BSs) that numerous 5G users can reach. The MMW-RF (Radio Frequency) link uses four MMW frequencies: 58.32, 60.48, 62.64, and 64.80 [GHz]. The present work offers designs based on different forms of optical communication systems. The performances of these designs are assessed using two powerful simulation tools, Matlab and OptiSystem. For the MMW-FSO link, the study analyses the Bit Error Rate (BER), the Communication Capacity (CC), and the RF-spectrum peak power. It additionally takes into account the performances of the MMW-RF link, such as the Required Signal-to-Noise Ratio (RSNR) at 5G users, the Receiver Sensitivity (RS) at 5G users, the BER at 5G users, the CC between 5G BSs and 5G users and Power Efficiency (PE) at 5G users. Data transmission has been tested on various connections of the proposed systems with an acceptable BER of 1e-9 on the MMW-FSO link. Without AT but in the presence of heavy fog, the average CC results obtained are 4.13e + 10 bps, 4.25e + 10 bps, 3.64e + 10 bps, and 4.11e + 10 bps for the first to fourth connections, respectively. With weak AT ( \({10}^{-17}\) ${10}^{-17}$ [m^−2/3]) and heavy fog, the average CC results are changed to 2.57e + 10 bps, 2.59e + 10 bps, 3.035e + 10 bps, and 3.15e + 10 bps, respectively. Under conditions of moderate AT ( \({10}^{-15}\) ${10}^{-15}$ [m^−2/3]) and heavy fog, the results become: 2.79e + 10 bps, 2.82e + 10 bps, 3.104e + 10 bps, and 3.120e + 10 bps respectively for the same proposed connections. Furthermore, the impact of the attenuation coefficient on the MMW-FSO link, which may have an impact on the performance of the proposed systems on the MMW-RF link between the 5G BSs and 5G users under different weather conditions must be taken into account. Connections one and two of the proposed systems outperform connections three and four in terms of their capacity to accommodate a greater number of 5G users. With an acceptable BER performance of 1e-3, connections three and four can accommodate a maximum of seven 5G users for each 5G BS operating within a bandwidth of 270 [MHz] when assigned distinct time slots. The ultimate goal is to advance next-generation communication technologies for a highly connected society with a manageable number of users.