An extended generalized rice model for wireless communications

The multipath component arriving at the mobile receiver cannot explicitly be of homogeneous nature due to nonuniform scattering caused by objects with irregular surfaces having various scattering properties. Another reason, which may contribute to this inhomogeneity, is the nonlinearity of the propagation medium. In this paper, a new general statistical small-scale model for wireless channels, which is affected by nonfrequency-selective fading, is proposed to describe the received signal level by taking into account the aforementioned effects. The advantageous physical interpretation of the model is introduced, and solutions for the probability density functions (PDFs) of the envelope and the phase as well as the cumulative distribution function (CDF) of the envelope are derived. In addition, the second-order statistics have been studied, and solutions for the level-crossing rate (LCR) and the average duration of fades (ADF) are obtained. The usefulness of the model is demonstrated by providing the best fit, compared with widely known models, to certain measurement data corresponding to a variety of real-world channel conditions. Furthermore, its validation is confirmed by simulation. Consequently, the extended generalized Rice model is applicable in wireless channels subjected to various conditions, and it can be preferable because of its outperformance.