Akademik Veri Yönetim Sistemi
IEEE Access, cilt.13, ss.202737-202744, 2025 (SCI-Expanded, Scopus)
Laser diode (LD)-powered luminaires are expected to become increasingly prevalent in residential and commercial environments. This trend creates an opportunity to develop visible light communication (VLC) systems, which are supported by the ultra-high bandwidth of LDs. In such a system, the main sources of distortion are two types of additive Gaussian noise: signal-dependent shot noise (SDSN) and relative intensity noise (RIN). The strength of the transmitted signal affects the variance of these noises. This paper introduces the first theoretical analysis examining the combined impact of SDSN and RIN on mutual information in LD-based VLC systems. First, we derived an expression for mutual information by considering both SDSN and RIN. Because this expression cannot be expressed in a closed form, its value was determined using numerical simulations. To address this challenge, a closed-form approximation is developed using Jensen's inequality, which facilitates the efficient performance evaluation and optimization of mutual information. The numerical results confirm the accuracy of the approximation for both the low and high signal-to-noise ratio (SNR) regions. In addition, it closely matches the actual values for the intermediate SNR levels. Furthermore, the numerical results indicate that RIN and SDSN significantly reduce the ability of LD-based VLC systems to achieve high data rates, thereby affecting their performance. In addition, the RIN is the primary source of noise, particularly when the transmitted power is at a higher level.