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关于陆地移动多址网络物理层的新论点

电信科学 1996年第3期12卷 18-23页

作者： Andrew J.Viterbi(qualcomm inc. San Diego, CA, USA) qualcomm inc 美国

本文描述了移动多址通信系统物理层的三个基础要求，并指出在符合此要求方面，扩频多址系统是最适当的选择。

关键词：移动通信 CDMA 信道测量多址通信

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码分多址（CDMA）系统设计面面观

电信科学 1996年第3期12卷 24-28页

作者： qualcomm inc.(qualcomm inc. San Diego, CA, USA) qualcomm inc 美国

本文简要介绍ＩＳ－９５ＣＤＭＡ系统的重要特性，然后论述ＣＤＭＡ系统规划的几个关键因素。包括通信容量、覆盖范围、传输质量和经济规模之间的利弊关系。同时，本文还说明，由于ＣＤＭＡ系统具有独特的扩频波形、功率控制和软切换等... 详细信息

本文简要介绍ＩＳ－９５ＣＤＭＡ系统的重要特性，然后论述ＣＤＭＡ系统规划的几个关键因素。包括通信容量、覆盖范围、传输质量和经济规模之间的利弊关系。同时，本文还说明，由于ＣＤＭＡ系统具有独特的扩频波形、功率控制和软切换等功能，因此，即使是最困难的工程技术问题也可以迎刃而解。

关键词：移动通信码分多址系统设计多址通信

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个人通信服务（PCS）的技术选择

电信科学 1996年第3期12卷 39-41页

作者： Jim Madsen(qualcomm inc.San Diego, CA, USA) qualcomm inc 美国

本文比较了ＣＤＭＡＰＣＳ与ＤＣＳ－１９００的覆盖范围、容量、成本、清晰度、灵活选择能力、用户满意程度，并给出了结论。

关键词：码分多址容量覆盖个人通信服务

码分多址（CDMA）技术和公用空中接口综述

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电信科学 1996年第3期12卷 6-17页

作者： Arthur H.M.Ross Klein S.Gilhousen(qualcomm inc.San Diego,CA,UsA) qualcomm inc 美国 Qualconum inc 美国

本文主要讨论数字移动通信中扩频码分多址技术，阐明了ＣＤＭＡ体制的优越之处，分析了ＣＤＭＡ的关键技术，全面介绍了ＣＤＭＡ系统设计的基本原则和ＩＳ－９５－Ａ空中接口标准的含义。

关键词：移动通信数字通信码分多址空中接口

Design and Analysis of Prioritized Medium Access Control Protocol for Backbone Routers in Wireless Mesh Networks

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Tsinghua Science and Technology 2012年第5期17卷 537-552页

作者： Lei Pan Hongyi Wu qualcomm inc. 1700 Technology Dr.San JoseCA 95110USA The Center for Advanced Computer Studies University of Louisiana at LafayetteLafayetteLA 70504USA

A Prioritized Medium Access Control （P-MAC） protocol is proposed for wireless routers of mesh networks with quality-of-service provisioning. The simple yet effective design of P-MAC offers strict service differentiation for prioritized packets. A Markov model is developed to yield important performance matrices including the packet blocking probability due to queue overflow and the packet reneging probability due to delay bound. It is further proved that the service time of P-MAC approximates exponential distribution, and can be effectively estimated. The analytic models with preemptive and non-preemptive schemes, validated via simulations, show that P-MAC can effectively support traffic differentiation and achieve very low packet dropping （both reneging and blocking） probabilities when the traffic load is below the channel capacity. When the network is overloaded, P-MAC can still maintain extremely stable and high channel throughput. Moreover, it is demonstrated that P-MAC performs superior in multihop networks, further proving the advantages of the proposed protocol.

关键词： Markov chain reneging medium access control binary countdown packet priorization network throughput Quality-of-Service (QoS) wireless mesh networks wireless routers

SHVC, the Scalable Extensions of HEVC,and Its Applications

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ZTE Communications 2016年第1期14卷 24-31页

作者： Yan Ye Yong He Ye-Kui Wang Hendry Inter Digital Communications Inc. qualcomm incorporated

This paper discusses SHVC, the scalable extension of the High Efficiency Video Coding (HEVC) standard, and its applications in broadcasting and wireless broadband multimedia services. SHVC was published as part of the second version of the HEVC specifi?cation in 2014. Since its publication, SHVC has been evaluated by application standards development organizations (SDOs) for its potential benefits in video applications, such as terrestrial and mobile broadcasting in ATSC 3.0, as well as a variety of 3GPP mul?timedia services, including multi?party multi?stream video conferencing (MMVC), multimedia broadcast/multicast service (MBMS), and dynamic adaptive streaming over HTTP (DASH). This paper provides a brief overview of SHVC and the performance and com?plexity analyses of using SHVC in these video applications.

关键词： HEVC SHVC broadcasting video conferencing video streaming

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空中交通控制系统网络状态估计器安全性分析

中南大学学报（自然科学版） 2013年第8期44卷 3216-3222页

作者：刘建良杨建刘为夷李舟中南大学信息科学与工程学院 qualcomm inc Santa Clara USA95051

线性状态估计器已被广泛应用于空中交通控制(ATC)系统监测和飞行器控制中。本文分析其在GPS欺骗、虚假数据注入和计算机病毒等网络攻击情况下的安全性。由于网络攻击很少发生,准确地对网络攻击进行建模几乎不可行。因此,分析所有可能的... 详细信息

线性状态估计器已被广泛应用于空中交通控制(ATC)系统监测和飞行器控制中。本文分析其在GPS欺骗、虚假数据注入和计算机病毒等网络攻击情况下的安全性。由于网络攻击很少发生,准确地对网络攻击进行建模几乎不可行。因此,分析所有可能的攻击情况,并在最坏的情况下分析状态估计器的安全性。最后进行仿真,结果显示:对于一类广泛应用的线性α-β估计器,提出的优化工具可识别所有可能的网络攻击中的隐蔽攻击,证明该方法的有效性。同时,方法也具有一般性,可适用于其他一些控制系统的安全性分析。

关键词：卡尔曼滤波器网络安全凸优化空中交通管制

Spatial Load Balancing in Wide-Area Wireless Networks

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ZTE Communications 2011年第4期9卷 49-54页

作者： Kambiz Azarian Ravindra Patwardhan Chris Lott Donna Ghosh Radhika Gowaikar Rashid Attar qualcomm inc. San Diego CA 92121 U.S.A

Load balancing is typically used in the frequency domain of cellular wireless networks to balance paging, access, and traffic load across the available bandwidth. In this paper, we extend load balancing into the spatial domain, and we develop two approaches--network load balancing and single-carrier multilink--for spatial load balancing. Although these techniques are mostly applied to cellular wireless networks and Wi-Fi networks, we show how they can be applied to EV-DO, a 3G cellular data network. When a device has more than one candidate server, these techniques can be used to determine the quality of the channel between a server and the device and to determine the Ipad on each server. The proposed techniques leverage the advantages of existing EV-DO network architecture and are fully backward compatible. Network operators can substantially increase network capacity and improve user experience by using these techniques. Combining load balancing in the frequency and spatial domains improves connectivity within a network and allows resources to be optimally allocated according to the p-fair criterion. Combined load balancing further improves performance.

关键词： CDMA 2000 EV-DO DO-RevC high rate packet data (HRPD) network load balancing (NLB) single-carrier multilink (SCML)

EFFECT OF A PROPELLER AND GAS DIFFUSION ON BUBBLE NUCLEI DISTRIBUTION IN A LIQUID

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Journal of Hydrodynamics 2012年第6期24卷 809-822页

作者： HSIAO Chao-Tsung CHAHINE Georges L. DYNAFLOW INC.

A multi-bubble dynamics code accounting for gas diffusion in the liquid and through the bubble wall was developed and used to study the modification of a bubble nuclei population dynamics by a propeller. The propeller flow field was obtained using a Reynolds-Averaged Navier-Stokes （RANS） solver and bubble nuclei populations were propagated in this field. The numerical procedure enabled establishment of the possibility of production behind the propeller of relatively large visible bubbles starting from typical ocean nuclei size distributions. The resulting larger bubbles are seen to cluster in the blade wakes and tip vortices. Parametric investigations of the initial nuclei size distribution, the dissolved gas concentration, and the cavitation number were conducted to ide- ntify their effects on bubble entrainment and the resultant void fractions and bubble distribution modifications downstream from the propeller. Imposed synthetic turbulence-like fluctuations unto the average RANS flow field were also used to study the effect averaging in the RANS procedure has on the results.

关键词： gas diffusion bubble entrainment propeller