volume | PIER Journals

Abstract

In optical communications, symbol error rate (SER) is a key indicator of system performance when data is transmitted over optical channels. Improving this rate is a major goal in the design of advanced optical systems, as many factors affect performance, including noise and optical impairments. One mathematical method proven effective for improving performance is the use of Laguerre polynomials. This study investigates the impact of variations in the polynomial parameters regarding Laguerre-Gaussian vortex beam (LGVB) on symbol error rate (SER) under weak, moderate, and strong turbulence conditions. The research uses numerical simulations to analyze the beam's intensity profiles and SER for various parameter combinations. Key findings show that specific parameter pairs yield superior SER performance, reducing error rates. The lowest SER under high turbulence is observed at (3,0) and (2,0) due to their spatially dispersed intensity profiles. Optimizing LGVB's polynomial parameters enhances SER robustness in turbulent FSO systems, offering a practical, non-hardware-based mitigation strategy. Simulation results for (n = 3, m = 0) show that the proposed beam configuration reduces SER to the minimum value compared to other Laguerre Gaussian Vortex beams with different values of radial index (n), and topological charge (m) under identical turbulence conditions (Cn² = 10^-12 m^-2/3). This work provides actionable insights for designing turbulence-resilient optical links, particularly in satellite-to-ground and long-range terrestrial communications.

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Dr. Ali Abdul Rahman Dheyab

Dr. Asmaa M. Aubaid

Dr. Ekhlas Kadhum Hamza

Dr. Hamid Sh. Aldulaimi