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1.
The development of radar by the US Army Signal Corps is traced as a prelude to presenting an account of the first use of radar in a US military action. This was the use of a newly developed Signal Corps radar set to detect the wave of Japanese aircraft as they approached the island of Oahu on the morning of Sunday, December 7, 1941  相似文献   

2.
The receipt of the Pioneer Award has given me a chance to look back over my professional life and the opportunity to take stock of how I helped shape a small part of the world. While I hope this process entertains my contemporaries, more importantly, I hope it stimulates those that are engaged in actively shaping the present. To describe the need for automatic picture transmission (APT), I must retrace the historical development of meteorological satellites. The idea for weather observations from a satellite originated with a small group of meteorologists at the U.S. Army Signal Corps Research and Development Lab. at Ft. Monmouth, N.J., and resulted in the design of Vanguard II. The Tiros and TOS series of satellites, and the design of Nimbus, followed soon thereafter. However, a faster picture dissemination than was available at that time was needed, and it was this necessity that sparked the development of APT. Nimbus was originally intended to be an operational system, but the advent of simpler, less costly stabilization systems made the Tiros evolution the clear winner. The geosynchronous weather satellites started nearly a decade later and evolved from the NASA Application Technology Satellite (ATS) series. All three systems, existing polar orbiting weather satellites, APT, and geosynchronous weather satellites, have changed meteorology and the reliability of weather forecasting profoundly.  相似文献   

3.
The operations of the US Army Corps of Engineers' Manhattan Project, started on September 17, 1942, are examined as an example of US success in R&D  相似文献   

4.
典型直升机是实施立体突击作战的重要力量,在火力支援、立体补给、综合勤务保障等方面发挥着重要作用。针对其构造形式和作战使用要求,直升机在低空超低空低速执行任务时,使用场景中面临低空和地面的多种威胁,致使其服役环境和作战环境更加恶劣。本文通过分析直升机在作战中面临的威胁特点,阐述在直升机设计和使用维护过程中,综合防护能力、环境适应能力、战伤抢修能力对直升机作战完整性的影响,通过合理设计机体结构,提升生存能力,提升海上、高原、沙尘等环境适应能力,建立完备的战伤抢修能力来保证直升机使用的完整性,满足使用需求。  相似文献   

5.
研究单快拍下双基地多输入多输出(Multiple—InputMultiple-Output,MIMO)雷达中相干信源的离开角(Directionofdeparture,DOD)与到达角(directionofarrival,DOA)联合估计问题。利用单快拍下双基地MIMO雷达的接收信号构造一组Toeplitz矩阵,利用这组ToepIitz矩阵重构一个信号矩阵,提出一种基于降维多重信号分类(ReducedDimensionMultipleSignalClassification,RD-MUSIC)的DOD与DOA联合估计算法。提出的算法能够有效估计相干信源以及非相干信源的角度,实现角度的自动配对,并且角度估计性能远优于FBSS—ESPRIT算法以及ESPRIT-like算法。仿真结果验证了算法的有效性。  相似文献   

6.
本文给出了灰色信噪比的定义,并将其用于多晶硅沉淀的数据分析,使表面缺陷和沉淀厚度在最佳条件下试验结果与灰色预估值更符合。  相似文献   

7.
本文在分析了扫描电机数学模型的基础上,设计了以DSP TMS320F2812为系统核心的伺服控制电路,文中详细介绍了DSP和A/D的接口、驱动电路及软件程序设计,并且通过相关的实验得出结论:该方案具有一定的可行性。  相似文献   

8.
旋翼塔信号传输系统是旋翼塔测试系统的重要组成部分,信号传输质量是决定测试系统测试数据真实性的最重要因素。由于旋翼试验塔采用长线传输,所以必须排除信号传输系统的干扰,必须对信号传输系统进行调试,以确保试验数据的可靠和准确。  相似文献   

9.
UQS独特码要求它被自然界偶然产生的概率尽可能小,根据UQS码的8条数学标准设计出标准判别的编码生成算法,编程得到了20个UQS码的精简码集,生成的UQS码均符合UQS标准,能够作为要害系统的解保密码。  相似文献   

10.
An improvement in high altitude communication with a small, rocket-borne sonde can be achieved by transmitting circularly polarized waves. Signal losses due to cross polarization of linear antennas can be reduced. Measured radiation patterns for instrument mounted linear and several helical antennas are presented. Flight data are discussed.  相似文献   

11.
本文提出了一种直流大电流的测量方法。直流电信号首先经磁路转换成磁场信号然后经霍尔传感器的磁场信号转换电压信号后,输出到仪表放大器和单片机进行处理并显示出被测电流。  相似文献   

12.
This summarizes the authors' research into the state-of-the-practice of software quality assurance (SQA) in software organizations throughout the Department of Defense (DoD). Information was obtained through personal visits to a limited number of software facilities and by utilizing a SQA questionnaire that was mailed to 27 DoD software organizations. Twenty questionnaires were returned from Army, Navy, Marine Corps, and Air Force organizations involved in the Life Cycle Software Support (LCSS) process. The survey developed information regarding such topics as: staffing; personnel qualifications; quality standards used; SQA responsibilities; error data collection; adequacy of existing documentation; staff composition; distribution of SQA effort; and workforce mix. In addition, a list of SQA ``Lessons Learned' was developed from comments made by DoD quality managers. The results of this study indicate a wide variance in the application of SQA within the DoD.  相似文献   

13.
Southwest Microwave, Inc. (SMI) introduced the world's first commercially viable bistatic microwave intrusion detection sensor in 1971. Bistatic microwave has become the paradigm for high security perimeters, and SMI products have become industry standards. With the introduction of the Intrepid Digital Microwave, SMI brings the latest in Digital Signal Processing (DSP) and power and data networking to this proven sensor technology  相似文献   

14.
传统的能量检测在接收信号为高斯分布下最优,其检测性能最终取决于信噪比。当信噪比下降时,检测性能必然恶化,而且这种恶化是不可避免的和难以改善的。为了改善弱信号的检测性能,本文同时利用了信号的三阶和二阶统计量构造一种双通道信号检测器,在强高斯噪声的背景下,只要弱信号蕴含有足够多的双谱信息,其检测性能将远远超过基于传统的能量检测器的性能。  相似文献   

15.
高速矢量处理机的设计与实现   总被引:1,自引:0,他引:1  
王俊  毛士艺  刘祥林 《航空学报》2001,22(3):212-216
为了满足海量实时处理需求,利用 Butterfly DSP公司的 BDSP91 2 4 /932 0矢量数字信号处理 ( DigitalSignal Processing,DSP)芯片组,设计和实现了一种高速矢量处理机,并给出了该矢量处理机的设计思想和性能指标。最后说明该处理机在合成孔径雷达 ( Synthetic Aperture Radar,SAR)脉冲压缩和其它领域的应用。  相似文献   

16.
频率步进雷达数字信号处理   总被引:49,自引:3,他引:49  
毛二可  龙腾  韩月秋 《航空学报》2001,22(Z1):16-25
综述了频率步进雷达系统设计与信息处理中的主要问题,包括系统参数设计、目标抽取算法、与Chirp子脉冲的兼容性、与圆锥扫描体制的兼容性等等,并论述了不同情况下多普勒效应的影响及其解决方法,提出了相应的数字信号处理方案。  相似文献   

17.
An Adaptive Detection Algorithm   总被引:6,自引:0,他引:6  
A general problem of signal detection in a background of unknown Gaussian noise is addressed, using the techniques of statistical hypothesis testing. Signal presence is sought in one data vector, and another independent set of signal-free data vectors is available which share the unknown covariance matrix of the noise in the former vector. A likelihood ratio decision rule is derived and its performance evaluated in both the noise-only and signal-plus-noise cases.  相似文献   

18.
现代高性能FPGA和DSP的不断出现,使得需要大数据量计算的雷达信号处理器向高度集成化和小型化方向发展成为可能,本文基于高性能FPGA(A ltera的Stratix II系列)详细介绍了一种数字波束形成器(DBF)、动目标检测器(MTD)和恒虚警检测器(CFAR)的单芯片集成设计方案,最后对其性能特性和改进方向做了初步的分析讨论,以满足更高性能要求时的设计实现。  相似文献   

19.
Eclipsing of received signals is analyzed for Interrupted Continuous Wave (ICW) radars. A probability density for the Signal to Noise Ratio (SNR) at the Doppler filter output is derived which incorporates eclipsing effects and a fluctuating target cross section model. The probability of detection as a function of SNR is calculated for typical ICW parameters and the magnitude of the detection loss due to eclipsing is assessed  相似文献   

20.
This paper presents an overview of the Ocean Engineering and Construction Project Office (FPO-1) of the Chesapeake Division, Naval Facilities Engineering Command design and construction of eight ocean towers. These towers are for the Charleston Tactical Aircrew Combat Training System (CTACTS). The offshore portion of the CTACTS provides the necessary facilities to accurately monitor and control the training of Navy, Marine Corps, and Air Force pilots, during aerial warfare training exercises. These offshore facilities are located 30 to 72 nautical miles east of northern Georgia in water depths ranging from 81 to 143 feet. In June, 1984, FPO-1 awarded the ocean tower design contract to Brown & Root Development, Inc. The final design was completed in August, 1985 and in January, 1986, FPO-1 awarded a contract to McDermott Marine Construction to fabricate and install the platforms. The installation is scheduled to be completed by mid-September, 1986.  相似文献   

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