摘要：The spatial selectivity of multipath fading channel impacts on the performance of the multiple antenna system. This paper investigates the three-dimensional (3-D) spatial selectivity of Rician channel in the angular domain to strive to alleviate the current lack of analytical studies. A 3-D model of the multipath angular power density (APD) for Rician channel is proposed. Then, the closed-form expressions of the 3-D unnormalized complex spherical harmonic coefficients and multipath shape factors are given based on the multipath APD using the theory of multipath shape factors. Finally, some important spatial fading statistics in the angular domain like the variance of the fading rate, spatial correlation, level crossing rate and minimum separation distance of antenna arrays are derived, and the impact of 3-D spatial angular directions on these spatial fading statistics is analyzed and simulated. The results provide useful insight on the analysis and design of the 3-D smart antenna arrays for the future fifth generation (5G) cellular networks.
关键词：Three-dimensional spatial selectivity; Rician channel; multipath shape factors; angular power density
