摘要
We investigate the average Level Crossing Rate (LCR) and Average Fading Duration (AFD) of multiuser single relay cooperation wireless uplinks over independent and non-identically distributed (i.ni.d) Rayleigh fading channels. We first present the statistical analyses of the first-hop equivalent envelope. Then, we investigate the LCR and AFD of an equivalent end-to-end envelope, and present the closed-form solutions to LCR and AFD, which are given with integral forms. Finally, we derive the Laplace approximations of LCR and AFD as well as the upper and lower bounds. The numerical results of LCR show that the upper bound is tight. For multiuser systems with different number of mobile users, the analyses indicate that the LCRs are approximately the same at the low level of the envelope. However, at the high level of the envelope there are reasonable differences among the curves of LCRs. Due to that fact that AFD is the inverse function of LCR, the results for AFD are the opposite.
We investigate the average Level Crossing Rate （LCR） and Average Fading Duration （AFD） of multiuser single relay co- operation wireless uplinks over independent and non-identically distributed （i.ni.d） Ray- leigh fading channels. We first present the statistical analyses of the first-hop equivalent envelope. Then, we investigate the LCR and AFD of an equivalent end-to-end envelope, and present the closed-form solutions to LCR and AFD, which are given with integral forms. Finally, we derive the Laplace approximations of LCR and AFD as well as the upper and lower bounds. The numerical results of LCR show that the upper bound is tight. For multi user systems with different number of mobile users, the analyses indicate that the LCRs are approximately the same at the low level of the envelope. envelope However, there are at the high level of the reasonable differences among the curves of LCRs. Due to that fact that AFD is the inverse function of LCR, the results for AFD are the opposite.
基金
supported by the Natural Science Foundation of China under Grant No.61261015
the 973 Project under Grant No.2013CB329104
the National Natural Science Foundation of China under Grants No. 61071090,No. 61171093
the Key Projects under GrantsNo. 2011ZX03005-004-003, No. BK2011027
the China Postdoctoral Science Foundation under Grant No. 2012M521105
Research Fund for the Doctoral Program of Higher Educationof China under Grant No. 20113223110001
the project 11KJA510001 and PAPD
