On statistics of the mobile rayleigh fading channel in non-isotropic scattering environments

Abstract

Scattering encountered in many wireless communications scenarios is non-isotropic. Assumption of uniform distribution of Power Azimuth Spectrum (PAS) in a non-isotropic scattering environment introduces significant errors on the second order channel statistics which are the basis for the estimation of some important receiver parameters. Moreover, there are certain applications in communications that rely solely on the statistics of the channel. In this contribution, we use the wellknown Jacobi-Anger expansion of the plane wave to develop a discrete-time generalized Rayleigh fading channel model that models the statistics of the channel in closed form in general, nonisotropic and isotropic, scattering environments. We compare the statistics of the channel for different commonly used non-isotropic scattering distributions, first, on the basis of autocorrelation, and, then, using a function (mutual information) of the correlational properties of the channel. In the latter case, through simulations, we observe the effect of varying different parameters like the angular spread, the block length of transmission and the mobile velocity which gives some interesting insights.

Diversity Gain and MIMO Capacity for Nonisotropic Environments Using a Reverberation Chamber

“…In addition, it has also been demonstrated that an AS of 60 is sufficient to achieve a system capacity close to the limit that corresponds to isotropic scattering [18]. The AS of a uniform distribution of the power in all angles corresponds to [9]. The AS is in fact confirmed to have an important effect on final MIMO capacity from Fig.…”