Modeling Crosstalk Coefficients in Orbital Angular Momentum-Multiplexed FSO Channels under Gaussian Pointing Errors

Crosstalk coefficients induced by pointing errors pose a significant challenge in orbital angular momentum (OAM)-multiplexed free space optical (FSO) communication systems. This paper presents a detailed investigation into the impact of Gaussian pointing errors on crosstalk coefficients within OAM-multiplexed FSO channels. Unlike previous studies which primarily focused on fixed strength of pointing error, our analysis encompasses a range of pointing error strengths. We propose closed-form expressions for the probability distribution function (PDF) governing the crosstalk coefficient, accommodating varying pointing error strengths. This analytical framework provides valuable insights into the behavior of crosstalk under different environmental conditions, facilitating the design and optimization of robust OAM-based FSO communication systems.