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车辆安全驾驶已得到人们的足够重视,高效的安全驾驶系统是未来智能汽车产业发展的主要技术支撑之一.相比其他无线通信技术,LTE技术在提供低时延、高可靠性以及移动性方面具有很大优势.由于D2D技术本身的短距离通信优点和直接通信方式使其能提供可控与可靠的本地服务,我们将提出基于LTE D2D discovery过程的V2V安全短距离通信方案,确保车辆间告警信息的广播时延小于100ms. 相似文献
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为减少车载信息传播时延,提出基于"分簇"的V2X车载广播信息传输策略。该策略以传输速率最大的车载用户作为"簇头",并采用注水算法为"簇头"分配功率。对车载信息进行紧急信息和非紧急信息分类传输。对于紧急信息,通过"簇头"实现信息中继转发,利用散射体一次、二次散射缩短通信时延;对于非紧急信息,在信道空闲时利用蜂窝通信进行广播。数值结果表明,相比于经典的LEACH算法,所提算法通过"分簇"提高信道利用率14.49%以上;相比于5G-V2X通信中虚拟小区,所提算法使得1 000 m内紧急信息通信时延平均减少2.21 ms。 相似文献
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在车路协同的4类技术(V2V、V2I、V2N、V2P)中,基于V2V的通信技术,是一种不受限于固定基站的车辆通信技术,旨在为运动中的车辆提供直接的一端到另一端的无线通信服务.在实际应用中,受限于车辆的自身原因(如接口未对外开放、不同车辆的接口协议不一致等),导致车辆无法直接与其他车辆互联,V2V变成了V2I+I2V.基于此,文章提出了一种基于V2V的自动驾驶汽车变道辅助应用方案,该方案旨在通过V2V技术来提高自动驾驶汽车变道的安全. 相似文献
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本文介绍了一种多信道共用通信与报警系统。该系统把车辆报警技术与集群通信技术相结合,将车载移动台的紧急报警信息传送到基地台,由监测计算机显示车载移动台报警信息,实现车辆监控。车载移动台和手持机还可以实现无线与无线、无线与有线之间的语音通信。 相似文献
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车联网移动无线数据通信系统的设计与实现 总被引:1,自引:0,他引:1
为了提高车联网移动无线数据通信能力,实现通过无线数据通信系统对车辆监控与导航,利用RFID和GPS技术,通过对车联网无线数据通信系统的结构分析,设计了车联网移动无线数据通信系统。重点研究了车载终端总体结构、车载终端通信模块、RFID感知通信模块、移动通信平台架构、定位追踪通信模块和远程控制通信模块。应用结果表明,该移动无线数据通信系统有较好显示能力和信息处理能力,能够处理导航、信息服务、车辆信息显示与辅助控制等功能的车载终端信息通信服务的需求。 相似文献
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本文介绍了一种把GPS技术与集群通信技术相结合,将车载移动台GPS接收机接收的定位信息,经过集群移动通信系统传送到基础台,由监测计算机显示车载移动台报警与定位信息,实现车辆监测,通过集群移动通信系统实现无线与无线、无线与有线间的语音通信,实现无线与无线、无线与有线间的数据通信,多功能通信指挥调度系统。 相似文献
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VANETs have been developed to improve the safety and efficiency of transportation systems (V2V communications) and to enable various mobile services for the traveling public (V2I communications). For VANET technologies to be widely available, security issues concerning several essential requirements should be addressed. The existing security architectures and mechanisms have been studied separately in V2V and V2I networks, which results in duplicated efforts, security modules, and more complex security architectures. In this paper, we propose a unified security architecture and its corresponding security protocols that achieve essential security requirements such as authentication, conditional privacy, non‐repudiation, and confidentiality. To the best of our knowledge, this paper is the first study that deals with the security protocol in V2V as well as the handover authentication in V2I communications. Our proposal is characterized by a low‐complexity security framework, owing to the design and unification of the security architectures and modules. Furthermore, the evaluation of the proposed protocols proves them to be more secure and efficient than existing schemes. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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目前超短波通信设备绝大多数采用模拟通信体制,而模拟通信存在抗干扰能力弱、通信质量差、保密性不强等缺点[1],这些缺点严重制约了通信装备性能的发挥和通信保障的顺畅。针对上述问题,文章设计了基于V.90标准的高速MODEM,核心是CX88168单片调制解调芯片,外加一片CX20463线路接口芯片和一片CX20437语音编解码芯片,可以实现模拟信号的数字化传输。 相似文献
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介绍了ASIC设计过程中电源,地压点个数的选择原则;列出了芯片内部电源、地布线宽度的计算方法;讨论了电源,地线在芯片上的走向;最后给出了设计实例。 相似文献
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《Digital Communications & Networks》2016,2(4):233-244
Among many safety applications enabled by Dedicated Short Range Communication (DSRC), truck platooning provides many incentives to commercial companies. This paper studies DSRC Vehicle-to-Vehicle (V2V) performance in truck platooning scenarios through real-world experiments. Commercial DSRC equipments and semi-trailer trucks are used in this study. We mount one DSRC antenna on each side of the truck. One set of dynamic tests and a few sets of static tests are conducted to explore DSRC behaviors under different situations. From the test results, we verified some of our speculations. For example, hilly roads can affect delivery ratio and antennas mounted on opposite sides of a truck can suffer from low delivery ratio at curved roads. In addition, we also found that antennas can sometimes suffer from low delivery ratio even when the trucks are on straight roads, possibly due to reflections from the nearby terrain. Fortunately, the delivery ratio can be greatly improved by using the two side antennas alternately. 相似文献
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Szu-Chi WangAuthor Vitae 《Ad hoc Networks》2012,10(2):199-211
In Vehicle-to-Vehicle (V2V) communications, the relatively large Doppler-spread poses a great thread to the system performance. In this paper, we propose a new physical layer air-link technology, which combines the advantages of CDMA and OFDM technologies. More specifically, we apply the column-wise complementary codes to the original OFDM-based physical layer design, which can effectively mitigate the Doppler effect under high-speed communication scenarios. The superiority of the new architecture is demonstrated by mathematical analysis and extensive computer simulations. The main contribution of this paper is two-fold. First, the presented analysis provides a more deep insight into the key performance bottleneck in the emerging short-range communications (DSRC) technology. Second, the proposed air link architecture can be implemented with a relatively low implementation complexity, which is desirable for practical applications. 相似文献
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李伟东陈小敏王梅朱秋明陈兵 《微波学报》2019,35(6):77-83
针对车-车(Vehicle-to-Vehicle, V2V)通信场景复杂多样且无线信号呈现三维传播的特点,提出了一种双簇散射体架构的三维非平稳随机几何信道模型(Geometry-Based Stochastic Model, GBSM)。该模型考虑了直射路径、单跳路径、多跳路径和虚拟等效链路,可适用于车联网通信环境各种信号传播场景。在此基础上,针对该模型理论推导了三维场景下信道的统计特性,包括归一化空时相关性、多普勒功率谱(DPSD)、电平通过率(LCR)和平均衰落持续时间(AFD)的理论表达式。仿真结果表明,推导的理论结果和数值仿真及实测结果都比较吻合,从而验证了理论推导的正确性及信道模型的有效性。该模型可用于车联网通信场景下无线通信系统的方案设计和性能分析。 相似文献
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软件测试是软件质量保证的一个重要环节,对于更为复杂的嵌入式软件测试而言,更需要一个阶段清晰控制好的开发测试模型。文章在分析讨论了已有的模型的基础上,进一步挖掘测试活动之间的并行性,尝试提出一种改进的V模型,该模型将软件测试贯穿软件开发周期的各个阶段,可以尽可能早的发现软件中的错误,同时结合实际的小型软件开发项目——GPRS扩展板通信实验,证明了该模型的正确性和有效性。 相似文献