The scientific community adopted Free Space Optical (FSO) communications with remarkable success. This much attention is influenced by FSO systems’ high data rate, unlicensed frequency bandwidth, cheap cost, and extreme security. FSO may be used in a variety of communication system applications because of these advantages. The primary channel degradation that impacts the effectiveness of the FSO connections is atmospheric turbulence (AT). Because of random fluctuations in the air refractive index during the communication period, there was atmospheric turbulence. The AT is described using a number of mathematical models. The weak turbulence modeled by the Log-Normal (LN). Generalized Low-Density Parity Check (GLDPC) codes and other channel coding techniques are therefore the best potential solutions for improving the performance of FSO communication links. In order to improve the weak turbulence FSO communication channel’s performance and lessen its impairments, this research proposes a new FSO system that makes use of two unique GLDPC decoders. All the parameters affecting FSO communications are also evaluated to show how the proposed system preserves state-of-the-art GLDPC coding techniques. The number of iterations used, the decoding time dissipated, the extracted throughput, and the convergence of the decoders are all preserved in order to assess the bit error rate (BER) of the proposed system in conjunction with innovative GLDPC decoder. The results showed that the novel GLDPC decoding technique in the proposed system outperformed the existing ones in the case of FSO communication channels across all comparison points considered in this study.