Double λ-κ-μ Distribution: Modeling and Performance Evaluation in Non-Homogeneous Environments

In this letter, we propose a general double $\lambda $ - $\kappa $ - $\mu $ distribution to model the fading characteristics of multipath cluster signals during relaying with line-of-sight components in non-homogeneous environments. By leveraging mixture Gamma distribution, the probability density function, cumulative distribution function, moment generating function, and higher-order raw moments of the signal-to-noise ratio are derived. Capitalizing on these, expressions for the amount of fading, average bit error rate and ergodic capacity are also obtained. The flexibility of the proposed model is demonstrated by its ability to encompass several well-known fading distributions as special cases, including double $\kappa $ - $\mu $ , double $\lambda $ - $\mu $ , and double Nakagami-m distributions, etc. Simulations further illustrate the effects of key parameters on signal quality.