Self-homodyne-direct-detection FSOC: a resilient approach to atmospheric turbulence and weather variations

Abstract Free space optics (FSO) technology is gaining attention for 6G and beyond networks due to its ability to provide secure data transmission, operate without the need for licensed spectrum, and support significantly higher data rates. Although the FSO system has various advantages, long-distance communication transmissions are inadequate. The dependability of FSO technology is predominantly influenced by various weather factors. This paper’s results seek to enhance the efficiency of FSO technology for long-distance communication. The present work utilised a combined methodology that mixes multi-beam combinations and self-homodyne direct-detection (SHDD) approaches inside a wavelength division multiplexed (WDM) FSO technology. The system is assessed through several implementations of single beam (SB), 4 multiple beams (MB4), and 8 multiple beams (MB8). This paper utilises the gamma–gamma (GG) channel model. The findings show that MB provided the best performance throughout a range of 1.6–12 km, with all lengths depending on the surrounding conditions. The link quality is determined by calculating the bit error rate (BER), Q factor and Eye height.