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Vehicular mobility patterns and their applications to Internet-of-Vehicles: a comprehensive survey

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Science China(Information Sciences) 2022年第11期65卷 5-46页

作者： qimei cui Xingxing HU Wei NI Xiaofeng TAO Ping ZHANG Tao CHEN Kwang-Cheng CHEN Martin HAENGGI School of Information and Communication Engineering Beijing University of Posts and Telecommunications Department of Broadband Communication Peng Cheng Laboratory China Mobile Research Institute Digital Productivity and Services Flagship Commonwealth Scientific and Industrial Research Organization (CSIRO) VTT Technical Research Center of Finland Department of Electrical Engineering University of South Florida Department of Electrical Engineering University of Notre Dame

With the growing popularity of the Internet-of-Vehicles(IoV), it is of pressing necessity to understand transportation traffic patterns and their impact on wireless network designs and operations. Vehicular mobility patterns and traffic models are the keys to assisting a wide range of analyses and simulations in these applications. This study surveys the status quo of vehicular mobility models, with a focus on recent advances in the last decade. To provide a comprehensive and systematic review, the study first puts forth a requirement-model-application framework in the IoV or general communication and transportation networks. Existing vehicular mobility models are categorized into vehicular distribution, vehicular traffic, and driving behavior models. Such categorization has a particular emphasis on the random patterns of vehicles in space, traffic flow models aligned to road maps, and individuals’ driving behaviors(e.g., lane-changing and car-following). The different categories of the models are applied to various application scenarios, including underlying network connectivity analysis, off-line network optimization, online network functionality, and real-time autonomous driving. Finally, several important research opportunities arise and deserve continuing research efforts, such as holistic designs of deep learning platforms which take the model parameters of vehicular mobility as input features, qualification of vehicular mobility models in terms of representativeness and completeness, and new hybrid models incorporating different categories of vehicular mobility models to improve the representativeness and completeness.

关键词： vehicular mobility pattern Internet-of-Vehicles (IoV) traffic flow spatial point process trajectory prediction machine learning deep learning

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Compressive Sensing Based Wireless Localization in Indoor Scenarios

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China Communications 2012年第4期9卷 1-12页

作者： cui qimei Deng Jingang Zhang Xuefei Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Ministry ofEducation Beijing 100876 P. R. China

The sparse nature of location finding in the spatial domain makes it possible to exploit the Compressive Sensing (CS) theory for wireless ***-based location algorithm can largely reduce the number of online measurements while achieving a high level of localization accuracy,which makes the CS-based solution very attractive for indoor ***,CS theory offers exact deterministic recovery of the sparse or compressible signals under two basic restriction conditions of sparsity and *** order to achieve a good recovery performance of sparse signals,CS-based solution needs to construct an efficient CS *** model must satisfy the practical application requirements as well as following theoretical *** this paper,we propose two novel CS-based location solutions based on two different points of view:the CS-based algorithm with raising-dimension pre-processing and the CS-based algorithm with Minor Component Analysis (MCA).Analytical studies and simulations indicate that the proposed novel schemes achieve much higher localization accuracy.

关键词： wireless localization fingerprinting compressive sensing minor component analysis received signal strength

Traffic balancing over licensed and unlicensed bands in heterogeneous networks

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Journal of Communications and Information Networks 2016年第2期1卷 115-124页

作者： LI Zhen cui qimei cui Zhiyan ZHENG Wei National Engineering Laboratory for Mobile Network Security Beijing University of Posts and TelecommunicationsBeijing 100876China

The rapid boosting in mobile traffic and the scarcity of available radio spectrum have hindered the improvement of capacity in cellular *** is necessary to discover an appropriate coexistence between cellular and other radio access technologies(mainly Wi-Fi)to offload the high traffic on to unlicensed *** with joint time and power allocation to devices,a non-convex problem is modeled to maximize the throughput as well as guarantee the desired user satisfaction.A two-step traffic balancing scheme is proposed to derive the *** also focus on the inner competition among cellular users instead of traditional competition between cellular and Wi-Fi in the unlicensed ***,simulation results show the effectiveness of the proposed two-step traffic balancing scheme.

关键词： licensed-assisted access using LTE traffic balancing unlicensed band time allocation

Coexistence Evaluation of LTE with Active Antenna System

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Communications and Network 2013年第3期5卷 217-222页

作者： Fei Xue qimei cui Ting Fu Jian Wang Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications

Due to the new radio architecture of Active Antenna System (AAS), the LTE BS equipped with AAS will have more flexible RF planning than that equipped with passive antenna. However, the new RF characteristic of AAS will have potential impacts on the existing BS RF requirements, which is imperative to be evaluated. In this paper, general antenna pattern and spatial Adjacent Channel Leakage Ratio (ACLR) are introduced considering the new RF features of AAS, and the impacts of AAS on BS performance are analyzed based on the AAS fundamental applications. System-level coexistence simulation is conducted to evaluate the RF features of transmitter and receiver of AAS on BS performance. Simulation results show that RF feature of spatial ACLR of AAS transmitter has little impact on throughput loss in victim system and ACLR of 45 dB per transmitter of AAS can fully meet the coexistence requirement;RF feature of in-band blocking level of individual receiver of AAS is higher than that of receiver of BS equipped with passive antenna around 1-4 dB, which imposes harder requirement to design the channel selection filter in the individual receiver of AAS, thus in-band blocking requirement needs to be redefined for AAS BS in the existing 3GPP specification.

关键词： Coexistence Evaluation AAS LTE Spatial Characteristics

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大数据驱动的绿色通信网络

深圳大学学报（理工版） 2013年第6期30卷 557-564页

作者：张平崔琪楣北京邮电大学信息与通信工程学院北京100876

分析当前网络面临的巨大挑战,研究如何有效承载大数据,确保用户服务质量(quality of service,QoS),降低能源消耗,实现绿色通信.指出移动互联网的飞速发展正在加剧其对人类数字生活的影响,推动未来网络在架构设计与网络优化中的变革和发... 详细信息

分析当前网络面临的巨大挑战,研究如何有效承载大数据,确保用户服务质量(quality of service,QoS),降低能源消耗,实现绿色通信.指出移动互联网的飞速发展正在加剧其对人类数字生活的影响,推动未来网络在架构设计与网络优化中的变革和发展.探讨面向用户行为和业务特征的大数据建模与分析,无线接入网络虚拟化与业务动态适配理论,保证QoS条件下基于能效的网络资源管理及若干开放性问题,为绿色网络通信研究指出方向.

关键词：通信与信息系统绿色通信大数据网络虚拟化资源管理网络优化能效业务动态适配

Capacity analysis and optimal power allocation for coordinated transmission in MIMO-OFDM systems

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Science China(Information Sciences) 2012年第6期55卷 1372-1387页

作者： cui qimei 1,HUANG XueQing 1,LUO Bing 1,TAO XiaoFeng 1 & JIANG Jun 2 1 Key Laborary of Universal Wireless Communications,Beijing University of Posts and Telecommunications,Beijing 100876,China 2 StarPoint Communication Software Company Ltd.,Beijing 100102,China Key Laborary of Universal Wireless Communications Beijing University of Posts and Telecommunications Beijing China StarPoint Communication Software Company Ltd. Beijing China

Coordinated transmission in multicell coordination networks has attracted much attentions in recent *** the paper,we investigate one open problem in the above area,which is concerned with how to solve the closed-form optimal power allocation scheme of coordinated transmission in downlink orthogonal frequency-division multiplexing (OFDM) systems with multiple antenna configurations and individual power constraints.A frequency-selective fading multiple-input multiple-output (MIMO) channel is *** derive the closed-form solutions of sum-rate capacity and optimal power allocations for coordinated transmission under the diversity case and the multiplexing case by solving the constrained optimization *** simulations are performed to verify the derived theoretical conclusions by means of comparing the proposed optimal power allocation (OPA) scheme with the other two typical power allocation *** is the power allocation scheme combining traditional water-filling with equal power (WS-EF PA).The other is equal power allocation (EPA) scheme.

关键词： coordinated multi-point transmission multicell cooperation capacity analysis MIMO-OFDM power allocation frequency selective MIMO channel

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RIS辅助的混合RF/THz系统性能分析

通信学报 2022年第1期43卷 49-58页

作者：黎赛杨亮崔琪楣于思源湖南大学信息科学与工程学院湖南长沙410082 北京邮电大学信息与通信工程学院北京100876 哈尔滨工业大学航天学院黑龙江哈尔滨150001

针对太赫兹(THz)链路传输距离短的问题,研究了智能反射表面(RIS)辅助的混合双跳射频(RF)/THz系统的性能。RIS用于增强信号强度,从而提升系统性能。采用固定增益放大转发协议,推导了混合RF/THz链路端到端信噪比的累积分布函数和概率密度... 详细信息

针对太赫兹(THz)链路传输距离短的问题,研究了智能反射表面(RIS)辅助的混合双跳射频(RF)/THz系统的性能。RIS用于增强信号强度,从而提升系统性能。采用固定增益放大转发协议,推导了混合RF/THz链路端到端信噪比的累积分布函数和概率密度函数表达式。利用这些统计特性,进一步推导了该混合中继系统的中断概率、平均误码率和平均信道容量的分析表达式。此外,还对中断概率和平均误码率进行了渐近分析,获得了混合RF/THz系统的分集度。仿真结果表明,RIS可以有效提高混合RF/THz系统的性能。此外,系统的性能还与信道衰落参数、指向误差和距离有关。

关键词：可重构智能表面太赫兹通信混合双跳系统性能分析

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EXIT analysis of M-algorithm based MIMO detectors and LDPC code design optimization

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Science in China(Series F) 2009年第12期52卷 2248-2258页

作者： YOU MingHou1,2, TAO XiaoFeng1,2, cui qimei1,2 & ZHANG Ping1,2 1 Wireless Technology Innovation Institute, Beijing University of Posts and Telecommunications, Beijing 100876, China 2 Key Laboratory of Universal Wireless Communications, (Beijing University of Posts and Telecommunications), Ministry of Education, Beijing 100876, China Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing China Key Laboratory of Universal Wireless Communications (Beijing University of Posts and Telecommunications) Ministry of Education Beijing China

This paper investigates joint design and optimization of both low density parity check （LDPC） codes and M-algorithm based detectors including iterative tree search （ITS） and soft-output M-algorithm （SOMA） in multiple-input multiple-output （MIMO） systems via the tool of extrinsic information transfer （EXIT） charts. First, we present EXIT analysis for ITS and SOMA. We indicate that the extrinsic information transfer curves of ITS obtained by Monte Carlo simulations based on output log-likelihood rations are not true EXIT curves, and the explanation for such a phenomenon is given, while for SOMA, the true EXIT curves can be computed, enabling the code design. Then, we propose a new design rule and method for LDPC code degree profile optimization in MIMO systems. The algorithm can make the EXIT curves of the inner decoder and outer decoder match each other properly, and can easily attain the desired code with the target rate. Also, it can transform the optimization problem into a linear one, which is computationally simple. The significance of the proposed optimization approach is validated by the simulation results that the optimized codes perform much better than standard non-optimized ones when used together with SOMA detector.

关键词： MIMO systems iterative receiver LDPC codes code optimization EXIT charts M-algorithm

An Effective Channel Estimation Method in Multi-band UWB System

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An Effective Channel Estimation Method in Multi-band UWB Sys...