The Department of Commerce's National Telecommunications and Information Administration (NTIA) led an interagency group to determine the viability of accommodating commercial wireless broadband in the 1755-1850 MHz band. While the analyses summarized in this report indicates there are a number of challenges to repurposing, NTIA concludes that it is possible to repurpose all 95 megahertz of the band. This analysis results from an eight-month evaluation process led by NTIA and engaging, via the Policy and Plans Steering Group (PPSG), the predominant federal agency users of this band. Each federal agency analyzed and documented its ability to relocate systems, associated costs, and anticipated periods of transition. In conducting the analysis, NTIA and the federal agencies endeavored to protect critical federal operations from disruption and to reach comparable capability via other spectrum, commercial services, or means that do not utilize spectrum, where appropriate.

关键词：通信；无线通信系统；宽带；可行性分析

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A wireless local area network (WLAN) is a group of wireless networking devices within a limited geographic area, such as an office building, that exchange data through radio communications. WLAN technologies are based on the IEEE 802.11 standard and its amendments.1 The fundamental components of an IEEE 802.11 WLAN (hereafter referred to as a WLAN in this publication) are client devices, such as laptops and smartphones, and access points (APs), which logically connect client devices with a distribution system, typically the organizations wired network infrastructure. The purpose of this publication is to help organizations improve their WLAN security by providing recommendations for WLAN security configuration and monitoring. This publication supplements other NIST publications by consolidating and strengthening their key recommendations.

关键词：通信；无线通信；局域网；无线电通信；无线网安全

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The design of reliable SatCom systems becomes critical, especially in the Q/V and W bands in which atmospheric fades are so strong that the traditional planning approach based on fixed power margins is no longer effective either because of technological constraints and/or extremely high costs. In this scenario, smart solutions known as Fade Mitigation Techniques (FMTs) are mandatory to optimize the system or to guarantee high-availability of the system even under extreme atmospheric conditions. This, in turn, triggers the need of more complex models not only aiming at accurately and reliably predicting the attenuation caused by all atmospheric constituents (gases, clouds and hydrometeors), but also able to simulate complex systems implementing FMTs and to estimate their performance in enhancing the delivered Quality of Service (QoS). This research activity focused on the performance evaluation of SatCom systems operating in the Q/V and W bands.

关键词：通信；性能测试；卫星通信；衰落缓解技术；带宽

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This paper provides a framework that can be used to develop technical assistance tools to help employers (including government contractors) design, purchase, lease, maintain and use ICT that is accessible to and usable by people with disabilities and others. More specifically, the Framework can be used as a tool for self-assessment to make easy point-by-point comparisons with current strategies and practices. In addition, the Framework can help a company develop a corporate-wide, comprehensive strategic plan (affirmative action program, where applicable) for adopting and implementing accessible ICT policies, practices and procedures for assessing progress made over time and ensuring continuous improvement. Further, the Framework can be used as a tool for internal staff development and training. In addition to the Framework, the paper also includes a comprehensive Benchmarking Tool, located in the Appendix, which companies could use to conduct a self-assessment and create their own corporate-wide, comprehensive strategic plan (affirmative action program, where applicable), including accountability mechanisms and methods for ensuring continuous improvement. This Benchmarking Tool is organized in accordance with the key components of an Accessible ICT Strategic Plan.

关键词：通信；工作主动性；访问技术；ICT；框架

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In disadvantaged grids, communication resources are scarce and variable. Thus, it is important that middleware and applications are able to adapt to the available capacity. This means that knowledge of the networking environment the C2 software is operating in is of great importance. Monitoring of networks carrying data is important in improving quality of service. There are two main types of monitoring: monitoring in the planning phase; and monitoring during deployment. Here, it is important to know the current load (e.g., link utilization) to be able to shape and control data traffic in a coherent manner. There exist many solutions capable of doing this, but they are mostly geared towards use on the Internet and in corporate networks. Sending data to and from mobile units, like military vehicles moving in a combat zone, provides challenges that may make some current tools unsuitable. In this paper, we focus on freely available tools, and attempt to identify which tools are suitable for the planning phase and which are suitable for the deployment phase in disadvantaged grids.

关键词：通信；带宽；指挥与控制系统；通信协议

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This research expands upon this understanding by determining the point at which voice traffic is no longer feasible in an ad hoc environment and determines which audio codec is best suited for MANETS. The MANET simulation environment is established using OPNET. Varying combinations of workloads are submitted to the MANET to capture voice performance within a stressed environment. Performance metrics are compared against established benchmarks to determine if thresholds for unacceptable voice quality are exceeded. Performance analysis reveals that VoIP communication using G.711 is not sustainable at walking (1.5 m/s) or jogging (2.5 m/s) speeds when three simultaneous streams are used. Also, G.729a is determined to be the best suited codec for MANETs since it significantly outperforms the other codecs in terms of packet loss and end-to-end delay.

关键词：通信；通信和无线电系统；移动自组网络；语音通话；实验设计

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We present the results of a two year project focused on a common social engineering attack method called 'spear phishing'. This project focused on a proactive approach to spear phishing. To create an effective, user-specific spear phishing email, the attacker must research the intended recipient. We believe that much of the information used by the attacker is provided by the target organization's own external website. Thus when researching potential targets, the attacker leaves signs of his research in the webserver's logs. We created tools and visualizations to improve cybersecurity analysts' abilities to quickly understand a visitor's visit patterns and interests. Given these suspicious visitors and log-parsing tools, analysts can more quickly identify truly suspicious visitors, search for potential spear-phishing targeted users, and improve security around those users before the spear phishing email is sent.

关键词：通信；电子邮件；网络安全；网络钓鱼；攻击

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A system and method of use is provided that includes: receiving configuration information from an unmanned underwater vehicle (UUV); automatically configuring a launch control console (LCC) according to the configuration information; and providing a graphical interface for a user to command the UUV to perform at least one task. The automatic configuration includes formatting commands and the graphical interface to suit a vehicle type and components of the UUV. Other embodiments include: aligning a navigation system in the UUV; selecting a mission; activating components in the UUV corresponding to the mission; and launching the UUV on the mission. Further embodiments include: downloading at least one preset associated with the UUV; modifying the presets; and displaying a status of components and a log of messages on the graphical interface.

关键词：通信；通信和无线电系统；水下作业车；水下导航

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This paper presents potential and actual advantages of using DTN for Earth science missions based on results from multiple demonstrations, conducted by the Communications, Standards, and Technology Laboratory (CSTL) at NASA Goddard Space Flight Center (GSFC). Demonstrations included two flight demonstrations using the Earth Observing Mission 1 (EO-1) and the Near Earth Network (NEN), a ground based demonstration over satellite links to the Internet Router in Space (IRIS) payload on Intelsat-14, and others using the NASA Tracking Data Relay Satellite System (TDRSS). Real and potential findings include increased flexibility and efficiency in science campaigns, reduced latency in a collaborative science scenario, and improved scientist-instrument communication and control.

关键词：通信；通信卫星；地球科学；有效载荷；延迟容忍网络

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The feasibility and performance of complex ICA to extract a weak co-channel interfering communications signal from a television broadcast signal is investigated in this thesis. The performance of three algorithms, complex maximization of non-Gaussianity (CMN) by Novey et al., RobustICA by Zarzoso et al., and complex fixed-point algorithm (CFPA) by Douglas, over varied interference-to-noise ratios (INR) for a fixed signal-to- interference ratio (SIR) is obtained by simulation. The communication signals examined for the weak interferer are binary phase-shift keying (BPSK), four- level rectangular quadrature amplitude modulation (4-QAM), and 16-level rectangular quadrature amplitude modulation (16-QAM), and the television broadcast signals are North American standard, Advanced Television Systems Committee (ATSC) and European standard, Digital Video Broadcasting - Terrestrial (DVB-T). Improved performance and sensitivity to the prewhitening step present in the ICA implementations are shown as the number of sensors increases.

关键词：通信；独立分量提取；无线电信号；同信道干扰

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