Channel modeling and pointing error mitigation in inter-satellite optical links using a dynamic beam waist adjustment method

Abstract

Inter-Satellite Optical Wireless Communication (IS-OWC) offers high-capacity links but suffers severe performance degradation due to pointing errors caused by satellite vibrations and jitter. To address this challenge, this paper presents a comprehensive channel modeling framework for IS-OWC links under pointing errors and proposes a Dynamic Beam Waist Adjustment (DBWA) technique that adaptively mitigates these impairments in real time without requiring prior statistical knowledge of the channel. Based on the proposed model, closed-form expressions are derived for performance metrics, including the average bit error probability, average bit error rate, and outage probability, under both non-coherent OOK and coherent BPSK modulation schemes. Monte Carlo simulations validate the analytical derivations and demonstrate that DBWA achieves up to a 46.6% improvement in channel gain and orders-of-magnitude reductions in error probability and outage compared to conventional fixed-waist configurations. Numerical results under varying pointing error levels, link distances, operating wavelengths, and receiver aperture sizes confirm the robustness and generality of the proposed framework. To the best of our knowledge, this work provides the first comprehensive analytical performance analysis of DBWA-equipped IS-OWC systems. The proposed method is computationally efficient, robust to misalignment, and establishes a foundation for reliable next-generation inter-satellite and deep-space optical networks.