计算机行业收入增速缓慢。2014 年1-2 月，计算机行业实现销售收入3222.7 亿元，同比增长-1.7%。1-3 月，全国电信业务总量完成4179.8亿元，同比增长15.2%；三家基础电信企业电信主营业务收入累计完成2908.3 亿元，同比增长6.5%，比2013 年同期回落2.6 个百分点。移动话音业务收入、网间结算收入的负增长是拉低整体收入增速下滑的主要原因。

关键词：IT 通信；运行分析；行业分析；市场竞争分析；经营分析

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Navigation requires knowledge of current location and a planned destination. This is true with manned vehicles and unmanned vehicles. There are many ways to acquire the current location, including global positioning system (GPS), triangulation, radar, and dead reckoning. Today GPS is the most reliable and accurate navigation technique when there is a clear, unobstructed view of the satellite constellation. Various sensors can be used to perform indoor navigation; however, when the vehicle is autonomous the sensors need to provide the exact location to the system. This research determined if using a template replay strategy has the same RNR performance as using an analog noise source. Using the template replay approach, each RNR node has a priori knowledge about the transmitted waveforms of other nodes. The analysis here revealed that modifications do not significantly alter RNR functionality. The analysis revealed that even at SNIR equal to 0 dB, there are no parameters that can be reliably extracted other than transmitted signal bandwidth and transmitted template length; the transmitted message length was able to be extracted because the message was repeated over and over. If the message was not replayed the analysis showed that there would be no ability to extract parameters. Finally, by using the RNR to transmit digitally generated templates, digital communication is possible and the symbol error rate (SER) is traceable to simulated SER.

关键词：自主导航;数字通信;室内导航;截获概率低;多基地雷达

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The AeroMACS (Aeronautical Mobile Airport Communications System), which is based on the IEEE 802.16-2009 mobile wireless standard, is envisioned as the wireless network which will cover all areas of airport surfaces for next generation air transportation. It is expected to be implemented in the 5091-5150 MHz frequency band which is also occupied by mobile satellite service uplinks. Thus the AeroMACS must be designed to avoid interference with this incumbent service. Simulations using Visualyse software were performed utilizing a global database of 6207 airports. Variations in base station and subscriber antenna distribution and gain pattern were examined. Based on these simulations, recommendations for global airport base station and subscriber antenna power transmission limitations are provided.

关键词：移动通信系统;天线增益;航空运输;无线通信;仿真;

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Information and communication technologies (ICT), like all technologies, are catalysts for political change and potential conflict. The Internet effect continues to fuel the explosive growth of ICT, and has enduring implications. It has sparked the long fuse of an Information Revolution and a Social Network Revolution. This revolutionary wave is fundamentally altering both the structure of institutional arrangements and the behavior of bureaucratic organizations by transforming traditional tactics for organizing, communicating, collaborating, and participating in the political system. Does the accelerated rate of systemic change caused by the Internet effect create social cohesion, or cleavages that may lead to increased conflict. The purpose of this study is to determine, by qualitative as well as quantitative means, whether a causal relationship exists between the degree a society is connected via social media networks (Internet and the World Wide Web WWW) and the institutional capacities of central governance. Blending theory with data, a statistical regression model is developed to evaluate the degree and measure the magnitude of this relationship. The findings gleaned from this analysis suggest that a conditional causal relationship does exist between social connectivity and state capacity.

关键词：互联网;社交沟通;通信和广播系统;测量

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The use of individual Global Navigation Satellite Services (GPS, GLONASS, Galileo, and Beidou/COMPASS) for the position, navigation, and timing in the Space Service Volume at altitudes of 300 km, 3000 km, 8000 km, 15000 km, 25000 km, 36500km and 70000 km.

关键词：导航卫星；航天通信；全球定位系统；Glonass系统；卫星跟踪

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Recent investigations into the fundamental limits of mobile ad hoc networks have produced a physical layer method for approaching their capacity. This strategy, known as interference alignment, requires cooperation, rather than competition, among the transceivers in the network. Under ideal circumstances, every user can achieve reliable communication at rates approaching one half of the interference-free capacity. Unfortunately, prior research on interference alignment makes many assumptions that make it difficult to realize interference alignment in practice. This report summarizes the PI's work on realizing interference alignment in multiple-input multiple-output (MIMO) communication channels. The emphasis is on networks where clusters of users cooperate together, since this provides a good balance between network overhead and performance. One contribution was to devise a way to add new users to an existing cluster of interference aligned users. Different algorithms were devised as a function of the number of antennas in the network. Another contribution was to analyze interference alignment in a network with random clusters of users. The cases where interference alignment was preferred to other simpler communication strategies was characterized. Another contribution was to determine the impact of distributing the antennas. It was found that distributed antennas lead to higher performance with interference alignment, and new algorithms were designed to achieve that performance. A final contribution was to prototype an interference alignment network. A distributed prototype was constructed with over-the-air synchronization and feedback, demonstrating the viability of interference alignment for small networks in practice.

关键词：天线;集群;通信和广播系统;通信网络

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The emerging wireless world is expected to be characterized from the demand for new, diversified applications/services, the expanded use of wireless and the need for increased efficiency in resource provisioning and utilization. Therefore, the resource usage in an opportunistic manner would provide a solution towards this direction. Opportunistic networks (ONs) and Cognitive Management Systems (CMSs) for cellular extensions are one of the emerging communication paradigms in wireless mobile communications. For the cooperation of CMSs, specific mechanisms need to be defined in order to increase the accuracy of obtained knowledge on the context of the operational environment. Also, a cooperation mechanism is required for efficient coordination between the infrastructure and the devices in the scope of an ON. Therefore, Control Channels (CCs) are required for the exchange of information and the coordination between CMSs. Consequently, this work focuses on the definition of the needed interfaces that are introduced in order to enable communication between the cognitive management systems and also to the related groups of information that is needed to be conveyed between these systems in order to ensure proper interaction. Finally, an indication of the amount of information conveyed through CCs is provided in order to be able to assess the impact to the network of control-related transmitted information.

关键词：无线通信；互联网；认知管理系统；机会网络

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关键词：可重构系统；通信；吞吐量

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During Phase one Option period, Trex performed extensive research into THz-range passive and active component that will be required make the Phase two hardware. The design of a custom MMIC was completed so it could be ordered processed with the once a year Pizza mask process at UMS. These parts are expected to arrive later this year when the Phase 2 contract is awarded and results in a significant cost saving in the development of a custom mixer. In addition the source pricing for the MMIC amplifier was also completed. This process took much longer than expected and this will speed up the process of betting parts during the second phase of the program. In addition direction of the overall mechanical configuration was outlined to speed up the process for the detailed design that will be undertaken in the next phase of the program. The radios will be designed to communicate in a half-duplex at 3 Gbps and full duplex using TDD mode at 1 Gbps data rate. The details of the TDD mode being much more complex were looked into in more detail during the option phase.

关键词：毫米波千兆; 通信;收发器;无线链路

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This chapter introduces the Internet of Intelligent Things (IoIT), the future Internet of Things (IoT) with significant intelligence added to "things". We discuss the importance of Artificial Intelligence approaches to enable such Intelligent Communication Networks. Nowadays, sensor networks are becoming a reality, especially for remote monitoring of events in fields such as healthcare, military, forest integrity or prediction of seismic activity in volcanoes. Intelligent devices and sensors are also appearing, besides electronic home appliances and utilities, as gadgets to mobile phones or tablets. And some of these devices have capability to actuate on the world. This chapter is focused on surveying current approaches for the Internet of all these intelligent things connected and communicating. It addresses artificial intelligence techniques employed to create such intelligence, and network solutions to exploit the benefits brought by this capability.

关键词：智能物联网；互联网；通信；人工智能

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