雷达脉冲参数的测量与分选

在电子对抗条件下,如何在密集的电磁环境中实时地分离出各雷达辐射源信息、得到正确的测量参数是进行雷达干扰的关键。简要介绍了雷达脉冲参数包括载频、脉冲宽度、脉冲重复周期、脉冲幅度和脉内调制参数的测量方法和通过序列差值直方图算法进行雷达信号分选的原理,给出了在电子侦察系统中采用软件无线电技术,通过DSP完成雷达脉冲参数测量与分选的设计方案和工程实现。     

基于无线传感器网络的移动目标跟踪系统研究

脉冲多普勒雷达(PDR)是一个超宽带雷达系统,不仅能探测目标位置,也可通过多普勒效应测量其径向速度。然而,传统的雷达信号处理技术与极限计算和典型无线传感器微粒上的存储资源不相匹配。利用小型脉冲多普勒雷达作为传感器节点,通过设计一个新的目标跟踪系统来探索脉冲多普勒雷达和微型无线传感器节点的兼容性。该系统由几个PDR传感器节点组成,来检测移动目标的存在和位置,一个基站节点用来收集传感器节点的检测数据,一个算法来估计目标的位置。结果表明该系统有较小的偏差,可实现目标跟踪。     

宽带高效率Doherty 电路的雷达应用设计

针对未来多功能一体化雷达探测、通信等多样化需求,雷达系统的发射链路需要在探测和通信两种 不同应用下同时输出高效率特性。但是基于非恒包络的通信信号具有高峰均比特点,而雷达系统恒包络信号却可以在高的饱和功率点工作。要求发射链路的功放既能在饱和输出高效率,还要在回退功率处仍然具有高效率特性。文中的雷达发射通道设计中,使用10 W 内匹配式功率放大器,验证了同时具有雷达探测和无线通讯的宽带高效率Doherty 功放电路。功放电路对输入功分电路采用双节宽带设计, 并使用短路切贝雪夫阶梯阻抗变换结构设计输出合成网络, 使得Doherty 电路在功放原来14%相对工作带宽内具有回退高效率, 其中6 dB 功率回退效率最大提升10%, 并满足雷达工作特性参数要求。     

Millimeter wave backscatter from deciduous trees

Measurements of the millimeter-wave backscatter from deciduous (leafed) trees are explained using a simple scattering model. The backscatter from individual leaves was measured in the laboratory and used to justify the use of an average leaf radar cross section when computing the normalized radar cross section (NRCS) of tree canopies. NRCS measurements of canopies show that the direction in which incident radiation impinges on the canopy is an important factor in characterizing radar backscatter. Comparisons of measured NRCS values demonstrate that planophil and erectophil trees can be distinguished based on their backscatter at 215 GHz     

Motivations, Design and Business Models of Wireless Community Networks

In this paper we provide an integrated presentation of applications, technologies and business models for wireless community network together with design considerations and examples. An overview is given of the state-of-the-affairs of wireless community networks. Driving forces and stakeholders of the projects and the applications and services will be presented for some carefully selected cases. We suggest a design methodology and illustrate its application to an ongoing digital city project in Hungary. Relevant business models are also analyzed.     

FM-UWB for Communications and Radar in Medical Applications

UWB technology is a useful and safe new technology in the area of wireless body area network. There are many advantages of using UWB as a communication standard for biomedical applications. Due to very low radiated power (−41.3 dBm/MHz), low power consumption, good coexistence with the other existing instruments, Robustness to interference and multipath. Moreover, one specific UWB technology, namely Frequency Modulated (FM)-UWB, has also an important advantage, which make it even more convenient for medical applications, such as simple low cost design (FM, no receive LO, no carrier synchronization as in IR-UWB). UWB technology has been also proposed radar applications such as: Non-Invasive Heart and Respiration Rate Monitoring; Detection of Cardiac Arrhythmias; Detection of Pathological Respiratory Patterns, particularly in Sudden Infant Death Syndrome (SIDS) and Sleep Apnea; Multi-Patient Monitoring; Detection and Non-Invasive Imaging of Breast Tumors. However, pulsed radar are mainly used for these applications. The main issue that is addressed in this paper is the integration of sensing and communication using FM-UWB and radar technology so that a single device can be obtained for two different operational mode. We have show that FM-UWB as radar can meet the requirements of typical biomedical applications such as Non-Invasive Heart and Respiration Rate Monitoring. Advantages and challenges of this integration are shown. Future perspectives of this novel activity will be drawn.     

基于MBSE的雷达数字化系统设计方法

文中首先系统阐述了“基于模型系统工程冶(MBSE)这一新系统工程方法的概念内涵和主要特征,从简单实例详尽解释了MBSE的电子类产品建模过程;深入研究了针对雷达复杂系统的MBSE方法论具体运用,在基于MBSE研发流程改进的基础上利用达索V6的环境平台验证了两型雷达研发的完整过程,全面实现了由传统基于文档DBSE研发模式向基于模型的MBSE研发模式转变,对大型复杂军事电子装备如电子战、导航、通信等其他相关行业有推广示范作用。     

雷达软件测试管理平台的研究及应用

文中针对当前雷达产品软件测试现状,详细介绍了测试管理工具QC（Quality Center）在雷达软件测试模型、测试需求管理、测试设计执行和缺陷管理等主要软件测试管理方面的应用解决方案。该方案实现了雷达软件测试中各种测试资源的有效整合,可以大大提高雷达软件测试效率和测试质量,取得较好的测试项目管理效果。最后,结合雷达产品,给出雷达软件测试管理平台在雷达产品软件测试中的具体应用。     

智能天线技术及应用研究评述

智能天线是提高无线传输性能的一项关键技术,是无线通信领域持续的研究热点之一,其中部分研究成果已经在无线通信、雷达、电子对抗等广泛的领域获得了成功的应用,并且未来无线系统设计中会越来越多的采用智能天线技术.为此,文章首先简要回顾了有关智能天线技术的发展历史,介绍了其中主要的阵列处理算法原理,给出了基于软件无线电和FPGA/DSP等可重配置软硬件系统设计参考方案,通过一些设计实例分析了应用中的实际问题和解决途径,最后提出了有关这一技术领域未来发展的展望.     

TD-SCDMA 直放站无线通信控制方案开发与实现

在TD—SCDMA系统中,直放站实现低成本的室内覆盖和减少信号盲区,是不可或缺的一部分。直放站系统要通过无线通信模块进行控制信息的交互,无线通信控制方案的实现是直放站系统开发中极为重要的一环。基于成熟的TD—SCDMA终端基带芯片的直放站无线通信控制方案,需要对硬软件配置做出相应的调整。通信控制方案中一个重要环节就是协定无线通信模块与直放站监控系统的串口通信接口,设计串口通信软件模块,串口通信协议的设定后,就可以经济、并快速地完成无线通信控制方案的实现。     

A laboratory study of the electromagnetic bias of rough surfacescattering by water waves

The design, development, and use of a focused-beam radar to measure the electromagnetic bias introduced by the scattering of radar waves by a roughened water surface are discussed. The bias measurements were made over wide ranges of environmental conditions in a wavetank laboratory. Wave-elevation data were provided by standard laboratory capacitance probes. Backscattered radar power measurements coincident in time and space with the elevation data were produced by the radar. The two data sets are histogrammed to produce probability density functions for elevation and radar reflectivity, from which the electromagnetic bias is computed. The experimental results demonstrate that the electromagnetic bias is quite variable over the wide range of environmental conditions that can be produced in the laboratory. The data suggest that the bias is dependent upon the local wind field and on the amplitude and frequency of any background wave field that is present     

基于CDMA1X雷达数据传输研究

为提高雷达情报传输的灵活性、机动性,提出了基于CDMA1X的雷达情报传输系统,该系统以中国联通通信公司的CDMA无线网络平台为基础,实现雷达数据的传输。文中介绍了传输系统的结构和传输控制、数据通信等关键技术,阐述了系统的工作原理,给出了主要模块的功能结构图和软件设计思想,并对系统的主要性能进行了分析。最后,通过对大量雷达数据的仿真,表明该传输系统能够满足数据传输实时性、可靠性、安全性的要求,适合雷达应急通信和机动雷达的数据传输。     

基于CC2430的ZigBee无线网络节点设计

ZigBee无线网络结构简单、设计成本低廉,功耗低,并拥有简单而灵活的通信网络协议,应用非常广泛。采用集射频与微控制器于一体的片上系统CC2430作为ZigBee无线网络节点的核心器件,提出带功率放大器的ZigBee无线网络节点的系统设计方案,并给出该系统电路原理图。硬件测试结果表明,节点硬件接收灵敏度高,通信距离也较理想。     

无线城市：从热点服务到全面应用

目前大部分发达国家和地区均开展了无线城市的建设,但由于普遍缺乏较为成功的商业模式,业务应用较为单一,因此效果不够理想。我国无线城市的运营应基于全球无线城市的运营经验,必须把握几个关键点,即获取政府支持、创新商业模式、打造统一平台、丰富业务应用、强化网络支撑等。     

某型无线电雷达高度表综合检测系统的实现

根据某型无线电雷达高度表二线检测仪技术性能及使用要求,介绍了以工控机计算机和PXI总线为系统核心而研制的综合检测系统,包括该系统总体结构组成和各模块的设计思路。通过凌华PCI-9112多功能高速数据采集卡和信号调理电路对检测信号进行采集处理,完成了微波组件和控制电路以及检测系统的上位机软件的设计。该设计实现了简便友好的人机交互系统,已经在航空检测中使用并验证具有很高的实用价值。     

蓝牙技术在无线实验室网络中的应用

提出利用蓝牙技术组建蓝牙无线实验室网络方案,以实现实验室局域网的无线化,并省去了实验室内计算机和仪器设备之间的复杂连线.同时为实现DSP实验设备与计算机之间的无线通信,设计了蓝牙替代电缆模块, 给出了模块的硬件结构和软件设计.     

Laboratory Projects for Engineering Students with FPGA

This paper proposes a series of related laboratory projects to the image processing area through reconfigurable integrated circuits like FPGA (Field Programmable Gate Array). With the implementation of these projects, the students will not only develop skills in electronic design, they also will increase their knowledge as engineers, with the integration of electronic engineering and computer science in the design of reconfigurable hardware with FPGA's. The algorithms proposed in these laboratory projects, for the image processing, are coded in C++ and are implemented in the embedded microcontroller Microblaze.     

E-Shaped Patch Antennas for Multitasks/Uninterrupted 5G Communications

Wireless Personal Communications - The future communication system is a fifth generation (5G) wireless communication. This communication system requires an antenna with a simple design, low traffic...     

基于DS18B20的无线温度监测系统

针对目前温度自动化监测低功耗,小型化,无线化的发展趋势,设计并实现了基于数字温度传感器DS18B20的无线温度监测系统.采用了Nordic nRF超低功耗无线方案,通过nRF24L系列片上系统控制温度采集和无线收发.对几种热门无线技术进行了对比分析并介绍了温度采集和无线传输的硬件电路设计,下位机固件程序以及上位机的应用软件设计.系统体积小,功耗低,结构简单,扩展性好,在工业自动化与控制,仪器仪表检测以及医疗监护设备等方面有广泛的应用价值.     

基于微缩雷达应用的硅基毫米波片上天线

为研究小型化、微型化天线在现代无线应用中的集成趋势,对当前工艺水平下的毫米波段片上天线(AoC)设计进行了总结。从集成角度,对单片集成和混合集成的概念分别进行了优劣比较和讨论。作为一个单片集成技术方案的可靠候选,对硅基单片毫米波集成电路(SIMMWIC)技术进行了介绍,并给出了利用该技术实现的整流天线例子。通过单片集成的雪崩二极管发射机展示了如何利用三维电磁仿真工具设计及证明片上天线的性能,利用仿真和实际验证探讨了硅基毫米波片上天线的挑战和方法,为小型化雷达系统方案提供了一个稳固的基础。