Finite-SNR Diversity Gain Analysis of the Fluctuating Line-of-Sight Fading Channel Model

The presented research studies the finite-signal-to-noise ratio diversity gain (FSDG) of a novel statistical channel fading model (i.e., the fluctuating double-Rayleigh with line-of-sight (fdRLoS)), suitable for both wireless and optical communication systems' description. To accomplish this, a closed-form analysis of the average bit error rate (ABER) decrement was performed for various channel and system parameters. Several specific peculiarities of FSDG were observed (e.g., depending on the fading parameter, FSDG can be completely dominated by diversity gain reaching it only asymptotically, or can be much greater than diversity gain for fairly low SNR values). To verify the correctness of the analytical part, it was appended by its numerical simulation that demonstrated high correspondence. The identified effects can be of specific use for SNR-limited systems' optimization.