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学术报告通知应网络体系构建与融合北京市重点实验室主任温向明教授的邀请，加拿大皇家学会、加拿大工程院、加拿大国家工程研究院Norman Beaulieu院士将于6月24日来北京邮电大学作学术报告。欢迎校内广大师生踊跃参加。报告题目：Generalized Models for Fading With Diffuse Scatter Plus Line-of-Sight Components 主讲人：Norman Beaulieu 院士主持人：武穆清教授时间：2014年6月24日（星期二）上午10：00--11：30地点：校办公楼501会议室报告摘要： New applications, as well as user demands for improved quality of services, create a need for improved channel models and better understanding of existing channel models. In particular, high mobility wireless channels are sometimes not well characterized by the popular wireless channel models. This motivates revisiting some wireless channel models that may not have found widespread usage in the past, as well as developing new flexible models that extend popular methods in physical as well as intuitive ways. For example, while the Rayleigh fading model describes a diffuse multipath signal and the Rician fading model describes a diffuse propagation environment with a single line-of-sight (LOS) component, there may be applications where thereare two or more specular waves (components), giving rise to the two-wave diffuse power model (TWDP) of Durgin, Rappaport and de Wolf. While it can represent many practical wireless communication systems and has obvious added flexibility, the mathematics of this model are complex, and in particular, computation of this model's infinite series solution is problematic for certain choices of channel parameters. This leads to the use of approximations for the relevant statistics and distributions. In this talk, we find exact infinite series solutions for the statistics and distributions of the TWDP wireless channel as well as efficient and precise recursive algorithms for their computation. The overall solution is efficient and precise for all practical values of channel parameters. A second real wireless channel scenario we consider is the case where LOS propagation is present but more flexibility is required in modeling the diffuse propagation environment than the Rician distribution affords. Some researchers have used the Nakagami-m distribution for this case. However, we argue that the Nakagami-m distribution can neither physically nor mathematically represent a fading scenario with a LOS component. That is, the Nakagami-m fadingmodel can exclusively represent sums of diffuse waves in multipath propagation. We introduce a novel fading model that combines a LOS component with a diffuse fading component modeled by the Nakagami-m distribution. Solutions for the PDF of the proposed fading model are found in terms of infinite series and as a finite sum in terms of the hypergeometric functions. The behaviors of the new diffuse Nakagami-m with LOS distribution fading model are investigated and compared to the behaviors of the Rice, Nakagami-m and two-wave diffuse power(TWDP) fading models. We modify some existing LOS fading models and propose a second novel fading model. We consider a LOS propagation environment with a diffuse component, this time modifying the generalized Rician distribution. This novel fading model unifies the non-central chi, generalized Ricean and kappa-mu fading models. The new fading distribution is given in closed-form and the effects of the parameters of the probability density function on its shape and location are demonstrated. Expressions are derived for the cumulative distribution function, moments and K-factor. Comparison among these fading models shows the new fading distributions to be flexible models for a wireless channel with both LOS components and diffuse scatter components, allowing for adjustment of the severity of the fading channel modeled. 欢迎全校师生踊跃参加。校学术委员会网络体系构建与融合北京市重点实验室 2014年6月20日主讲人简介.doc

学术报告通知：Models for Fading With Diffuse Scatter Plus L