AES S盒的马尔可夫性质研究

对AESS盒的阶次运算进行了研究,发现AESS盒的连续状态转移是一个马尔可夫链,其256个状态可以划分为5个常返态闭集,状态周期分别为59,87,81,27,2。     

中小电视台硬盘自动播出的解决方案

播出系统是电视台不可缺少的重要组成部分一个台理的播出系统应综合考虑系统的安全性、应急能力播出功能。与电视台其他系统的连接扩展播出功能等技术指标以及系统造价等问题。     

无人机测控与信息传输有关系统问题探讨

测控与信息传输系统是无人机系统的重要组成部分,按照作用距离,系统可以分为微型无人机、极近程无人机、短程无人机、远程无人机的测控与信息传输系统。对系统设计中的有关系统问题进行了探讨,包括频率资源如何利用、测控和通信功能怎样综合以及系统的技术体制如何选择等。     

浅析电力通信综合网管系统设计

随着电力技术迅速的发展,通信网络、电力配置和应用日趋复杂,在这样的背景下,建立相应的电力通信综合网管系统显得尤为重要。文中简单介绍了通信综合网管系统的设计原则,分析了综合网管的功能目标与系统设计模式,从四个方面论述了综合网管系统各功能域的设计,包括故障管理功能、网络预警功能、维护管理功能以及性能管理功能设计。     

综合智能告警系统调度应用与改进建议

综合智能告警是智能电网调度技术支持系统中实时监控与预警类应用的重要功能,对电网事故处理有重要的提示、分析判断作用。电力调度已正式开展综合智能告警业务,对更快、更准确处理电网事故起了重要作用。文章对综合智能告警推图情况现状进行分析,并提出改进建议,杜绝综合智能告警推图在实际应用中漏推、多推等误推情况的发生。     

智能家庭安防预警系统的设计

智能安防系统是智能家居系统中较为重要的子系统,本文运用Arduino开发板、WiFi无线模块设计了一种智能家居安防系统。利用无线网络实现远程通信,综合实现了家居信息采集、远程报警等功能,可广泛应用于防火防盗、安全监控和安防等领域。     

电力GIS系统的设计与实现

电力GIS是我国电网建设需要使用的关键信息技术之一,广泛应用于电网建设规划、气象、配电管理等方面。该系统的主要功能是通过建立逼真的地理环境及重要的建筑物、杆塔、变电站等三维模型,沿布重要杆塔线路以达到建立完整的电网模型并实现空间分析功能的目的。系统采用Clipmap作为大规模地形渲染技术,成功地展示了高清的地理数据、模型等。系统实现了线路、电力设备的浏览、编辑、管理和信息显示输出等功能,增强了信息的科学管理和综合分析,有效地提高了电网的管理效率。     

论变综合自动化技术在变电站中的应用

变电站综合自动化是指利用先进的计算机技术,现代电子技术、通信技术和数字信号处理（DSP）等技术,实现对变电站主要设备和翰、配电线路的自动监视,测量,控制,保护以及与调度通信等综合性自动化功能。本文首先就变电站综合自动化系统应用技术、特点和实现的功能做了介绍,然后简单阐述了系统的组成和软件系统。     

66kv变电站综合自动化系统初探

变电站是电力系统中的重要系统设备部分,对于电力系统的配电电网运行有着重要的影响作用。变电站的综合自动化系统的实现对于电力系统运行过程中,无人值守情况下的电力系统运行安全以及电力故障的自动检修与排除都有着积极的作用。变电站综合自动化系统的实现与应用是对于电力系统配电电网运行需求的更好满足,同时也是电力系统发展的趋势。本文主要对于66KV变电站的综合自动化系统的结构功能以及应用情况进行分析研究。     

基于MIMO阵列的综合射频系统技术研究

综合射频系统集雷达探测、数据通信和电子干扰等多种功能为一体,显著提升武器平台在复杂战场环境下的生存能力和作战效能,是武器装备的重点发展方向。针对现有综合射频技术难以高效同时实现多功能等不足,提出构建基于多输入多输出(multi-input-multi-output, MIMO)阵列的综合射频系统。研究结果表明,通过充分利用MIMO阵列的空间自由度和波形自由度,基于MIMO阵列的综合射频系统能够同时实现多功能。将系统探测通信性能、反侦察抗干扰能力、兼容性等方面与传统综合射频技术进行对比,表明基于MIMO阵列的综合射频系统具有独特优势。对基于MIMO阵列的综合射频系统关键技术进行了梳理分析和展望。     

Multiband folded planar monopole antenna for mobile handset

This paper introduces a folded planar monopole antenna, which has a very low profile of about one twentieth of the wavelength of the lowest operating frequency. The effect is achieved by using a bended rectangular radiating patch and an inverted L-shape ground plane. The proposed antenna can be used in multiband operation, with omnidirectional radiation patterns for all operating bands. Its impedance bandwidth, determined by 10 dB return loss, covers almost all present wireless communication systems: Global System for Mobile Communication (GSM), Digital Communication System (DCS), Personal Communication System (PCS), Universal Mobile Communication System (UMTS), and Industrial Science Medical (ISM) band. This paper presents the design and experimental results of the proposed antenna. Moreover, the study also investigates the tuning effects of the geometry parameters on impedance matching.     

Octa-band internal monopole antenna for mobile phone applications

A low-profile monopole antenna covering the following frequency bands is proposed for mobile phone applications: Global System for Mobile Communications (GSM-900), Digital Communication System (DCS), Personal Communication Services (PCS), Universal Mobile Telecommunications System (UMTS), Wireless Broadband (WiBro), Bluetooth, Satellite-Digital Multimedia Broadcasting (S-DMB), and Wireless Local Area Network (WLAN) frequency bands in the 5.0 GHz range. Multiple resonators in a compact configuration have been used to realise the octa-band internal antenna within a volume of 2.08 cm³ that is very attractive for multifunctional slim handsets. Measured performances of a prototype antenna have been compared to predicted results.     

Novel Wideband Directional Dipole Antenna on a Mushroom Like EBG Structure

A new method to design thin wideband directional dipole antennas on electromagnetic bandgap (EBG) structure is introduced. At the heart of this method is the idea to understand and properly utilize the complex interactions between the dipole impedance and the EBG reflection phase characteristics. Using the proposed technique a thin wideband printed dipole is designed, fabricated and tested. The antenna can satisfy applications, such as Digital Communication System (DCS, 1.71-1.88 GHz), Global System for Mobile Communication (GSM, 1.85-1.99 GHz), Personal Communication System (PCS, 1.85-2.05 GHz), Universal Mobile Telecommunication System (UMTS, 1.92-2.17 GHz) and Wireless Local Area Network (WLAN, 2.4-2.485 GHz) within VSWR les 2.5:1. Antenna peak gain varies from 5.5 to 8.3 dBi from 1700 to 2500 MHz while the front to back (F/B) ratio is higher than 15 dB for an overall antenna size of 102 mm by 76.4 mm by 5.9 mm.     

美军F-22的先进航空电子系统

F-22“猛禽”战斗机将取代F-15成为美国空军的下一代空中优势战斗机。文中主要论述F-22“猛禽”战斗机的综合化航空电子系统（IAS）的分层设计、综合化体系结构以及主要设备，包括共用综合处理器（CIP）、APG-77雷达、通信、导航和识别（CNI）、电子战（EW）、外挂管理系统（SMS）、惯导系统（IRS）和控制与显示（C＆D）。最后还介绍了客错与恢复机制。     

基于气象威胁的无人机航迹规划方法研究

针对复杂气象条件下的无人机航迹寻优问题,用栅格法进行环境建模;在基本蚁群算法的基础上,用确定性选择与随机性选择相结合的方法对节点的状态转移规则进行改进.用精英蚂蚁系统、最大最小蚂蚁系统及最好最差蚂蚁系统思想更新信息素规则,对部分参数进行自适应处理,并将遗传操作融入航迹搜索过程中,同时对航迹进行平滑处理.仿真结果表明,改...     

GPS接收机应用于手机中所遇到的射频干扰

将GPS接收机嵌入到手机硬件中,GPS接收频率将与手机中其它射频源共存.这些射频源包括GSM,UMTS,WLAN和Bluetooth.指出这些射频源对GPS接收信号的干扰程度,以明确哪种射频源对GPS接收机的阻塞影响最大,成为提出相应的解决方案是关键.验证方法主要是由Texas Instrument提供的GPS评估板接收来自GPS卫星模拟器发出的GPS信息,由具备GSM,UMTS,WLAN,Bluetooth功能的手机分别对GPS评估板发出不同的射频传导信号.结果证明:主要验证了UMTS1 900 MHz作为手机发射源时,对GPS接收机的阻塞影响最大,对改善GPS接收机带通滤波器的性能,为抑制UMTS信号起到很好的作用.     

基于ETC和MTC高速公路组合式联网收费系统设计

在电子不停车收费系统(ETC)和我国现行的人工半自动收费系统(MTC)的基础上,提出了基于ETC和MTC的高速公路组合式联网收费系统的设计方案。本文对ETC车道和MTC车道的硬件系统(包括通信子系统、车辆自动分类子系统、视频监控子系统)和软件系统(包括ETC车道收费子系统、MTC车道收费子系统、收费站服务器系统、中心服务器系统和用户服务子系统)分别进行了阐述,验证了本系统的可行性。     

SOP集成技术的发展现状及其在毫米波系统中的应用

介绍了SOP(System On Package)集成技术,并与传统系统集成方法以及SOC(System On Chip)、MIP(Module In Package)、MCM(Mult i Chip Module)、SIP(System In Package)等微封装、微集成技术进行了比较和分析,揭示了SOP小型化、低成本、高可靠性、高性能特点。对SOP在毫米波系统应用、新材料和新工艺的进展进行了总结,结果表明SOP在毫米波系统中具有良好的应用前景。     

Compact PIFA for Mobile Terminals Supporting Multiple Cellular and Non-Cellular Standards

A novel multiband planar inverted-F antenna (PIFA) covering ten frequency bands has been proposed for personal wireless communications terminals. The design is based on the combination of various techniques that are used for designing multiband/broadband antennas. We used a shorted parasitic patch efficiently coupled to the driven patch, a quarter-wave resonator connected to the feed strip in parallel with the main patch, and four slits in the main radiator to excite various current modes in the antenna structure. The antenna is designed within a volume of 4.0 times 2.0 times 0.8 cm³ and it can be used to serve the following wireless communication systems: Global System for Mobile Communications (GSM-900), Digital Communications System (DCS), Personal Communication Service (PCS), Universal Mobile Telecommunications System (UMTS), WiBro at 2.35 GHz, Bluetooth, Satellite-Digital Multimedia Broadcasting (SDM-B) at 2.65 GHz, WiMAX at 3.5 GHz, and the two bands (5.15-5.35 GHz and 5.725-5.875 GHz) for the wireless Local Area Network (WLAN) standards. A prototype antenna was fabricated and tested for input reflection coefficient and radiation performances. The measured and simulated results have been presented and discussed. Important geometrical parameters determining the multiband performances of the antenna have been explained in the paper.     

Loadability in composite generation/transmission power-systemreliability evaluation

An approach to composite (generation and transmission) power-system reliability evaluation that is based on contingency enumeration and on a simulation process to assess the system state is introduced. Using an AC load-flow model, the analysis starts with a nonlinear optimization procedure to determine system loadability. System characteristics, constraints, and operator intervention are taken into account. The nonlinear optimization procedure uses the modified augmented Lagrangian technique. Reliability indexes evaluated for the system and load buses are: loss of load probability (LOLP), (statistically) expected demand not served (EDNS), loss of voltage probability (LOVP), and (statistically) expected voltage violation (EVV). Sample numerical results are presented for the IEEE Reliability Test System