The SCR-270-B on Oahu, Hawaii-reminiscences

One of the two members of the US Army Signal Corps involved reminisces about 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     

Not invented here? Check your history

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     

Prologue to radio position finding (RPF)

The author reminisces about the use of radar by the US Army in Hawaii and the detection of Japanese aircraft as they approached Oahu on December 7, 1941. He briefly discusses post-Pearl-Harbor radar activity     

Advances in bistatic radar (Willis, N.J. and Griffiths, H.D., Eds.; 2007) [Book Review]

The editors have collected a comprehensive set of monographs that provide insight into the more recent history of bistatic radar design and implementation. This volume combines improved details of the environment along with novel system applications. Each chapter is authored by radar experts who had the vision and motivation to tackle a daunting development problem, and share their view of the successes and remaining implementation challenges. The book is divided into two parts: Bistatic/Multistatic Systems and Bistatic Clutter and Signal Processing. The book is an essential addition to the modern radar engineer's library.     

A Statistical Evaluation of Aircraft Collision-Hazard Warning System Techniques in the Terminal Area

The rapidly increasing density of air traffic has created a demand for instrumentation to reduce the possibility of air catastrophes due to collision. The incidence of reported near-collisions is now estimated to be over 2000 per year in the United States, and represents a serious threat to the future growth of air travel. Since mid-1967, research has been conducted by NASA and the Research Triangle Institute to develop techniques for evaluation of collision warning systems and to determine the characteristics of the operational environment. Actual aircraft traffic data have been obtained by the FAA from the radar system at the Atlanta Airport. These data have been analyzed to determine encounter statistics which would result with various forms of warning criteria. This paper reviews the definition of several proposed warning criteria and presents the results of the statistical analyses of the data. Probabilities of encounter, encounter rates, and average encounter durations are determined for various definitions of the encounter.     

飞机失速告警系统发展技术综述

目的论述飞机失速告警系统的组成、原理、功能和对飞行安全的重要性;方法介绍国内外在飞机失速告警系统和飞机过失速机动与告警方面的研究进展;结果分析国内在飞机失速告警系统研究方面与国外的差距;结论指出为尽快缩短国内外相关领域的研究差距,需从飞机失速告警理论上、设计思路上和试验验证手段上做出进一步努力。     

频率步进雷达数字信号处理

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。     

Development of airborne moving target radar for long range surveillance

The following topics are discussed in the context of the development of an airborne moving target radar for long range surveillance: US Navy long range shipborne radar; Cadillac I airborne early warning (AEW) radar; Cadillac II airborne early warning (AEW) radar; airborne moving target indicating (AMTI) radar; related post-war radar activities; and the invention of the displaced center antenna. Among the topics studied is the use of a monopulse antenna in an MTI radar to remove the degradation of the MTI caused by rapid scanning of the antenna. A method of using a monopulse antenna for motion compensation in airborne MTI is discussed.<>     

分层结构的雷达告警设备软件测试方法

雷达告警设备是现代作战飞机不可或缺的雷达对抗设备,主要用于对敌方雷达威胁信号的告警.分析了分层结构的雷达告警设备软件的特点,借鉴集成测试中自底向上增量式集成策略,提出了一种综合运用调试、插桩和仿真的配置项测试方法.测试结果表明,方法对此类以数据处理功能为核心、分层结构设计的嵌入式软件测试,有很好的借鉴作用.     

机载预警雷达技术发展探析

分析了世界各国预警雷达发展概况,分别对一至四代预警雷达的功能等进行了研究;论述了新一代预警雷达的工作原理、雷达组成、功能、工作过程和技术特点;指出了机载预警雷达未来发展的关键技术,包括有源相控阵雷达技术、数字阵列雷达技术、共形相控阵技术,双/多频段雷达技术及先进的信号处理技术等。     

Aircraft trajectories considering radar range constraints

The problem of finding an optimal aircraft trajectory subject to constraints defining distance of detection to hostile radar stations is considered. The purpose is to find a trajectory minimizing the flight time between two given positions without hostile radar detection. The flight path is represented using a smooth curve in the form of a spline approximation. The spline representation is used to derive the heading- and bank angles of the aircraft. The position of the aircraft together with the bank- and heading angles are used for calculations of the radar detection range. Furthermore, an example in three dimensions when a Saab 105 approaches a radar station in level flight is investigated.     

Probability of Detecting Aircraft Targets

The statistics of aircraft radar cross section (RCS) are estimated by fitting members of the chi-square family of distributions to empirical distributions obtained from blocks of RCS data, each block of data corresponding to a particular aircraft azimuth aspect. The parameters of the fitted distributions vary with azimuth aspect angle, type of aircraft, and radar frequency. Detection probabilities based on the estimated statistics are calculated and compared with detection probabilities based on Rayleigh statistics. This comparison indicates that the average value of radar cross section has much more effect on probability of detection than the normalized variance of RCS, and in the usual situation tends to mask the effect of the normalized variance on probability of detection.     

飞机雷达天线系统隐身技术研究

分析了由飞机雷达罩、雷达天线和雷达舱内高频部件构成的雷达天线系统的散射特性,并研究了其隐身机理和隐身措施.提出了飞机雷达舱气动,隐身,结构一体化设计概念.     

MIMO雷达中一种降维MUSIC的相干角度估计算法

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。     

Broadcasting of a Digitally Coded List of Transponder Equipped Aircraft Scanned by FAA Ground Radars as a Means of Collision Avoidance, Navigation, Air Traffic Structuring, and Airfield Approach

An air traffic control system is proposed in which 1) all aircraft are equipped wit transponders, 2) FAA radar sites broadcast a digitally coded list of the identity, altitude, and coordinates of aircraft scanned, 3) each aircraft on receiving this list converts it into a PPI display with the blip of that aircraft branded and blips of off-altitude aircraft blanked, and 4) superimposed on this display are projected maps of airways appropriate to the particular radar and the aircraft altitude. This system could provide a fairly complete capability for air traffic control, structuring, navigation, and collision avoidance at a cost of about 3000 dollars per aircraft. It would replace most navigational and communication equipment now in use and could be operational in several years.     

基于FPGA＋DSP＋DDS芯片的雷达信号发生器设计

现代高科技战争对雷达系统设备的功能与性能提出了越来越高的要求，信号发生器作为雷达系统的重要组成部分也面临着更高的挑战，尤其是在体积、重量、功耗以及性能等方面要求越来越严格。分析了目前信号发生器的设计方法及其优缺点，并提出了一种基于FPGA＋DSP＋DDS芯片的雷达信号发生器设计方法，信号发生器具有频率分辨率高、噪声低、体积小、功耗低和控制简单等特点，且在某型产品中成功应用。     

Multiple-Target Monopulse Radar Processing Techniques

The problem of determining target parameters of a known number of radar targets falling in the same range-Doppler-angle-angle resolution cell is examined for the noise-free case. The required minimum number of radar beams is determined, based upon approximating the beam patterns by a Taylor series expansion, both for the general problem and for factorable beams. Signal processors for target position estimation are developed for the two-target case and equations are presented for the general case.     

飞行器目标频率响应散射特性

为研究飞行器目标散射频率响应特性和隐身、反隐身原理,对两种飞行器平板缩比模型进行了系列测试和计算研究,推导和验证了简单目标（金属球）的频率响应特性在飞行器目标上的适用性,并推广到如飞行器复杂散射体的分析。提出了划分瑞利区、谐振区、高频区的新方法,指出飞行器具有隐身能力极限的概念;研究了目标多频散射的极化特性,发现频率降低时,水平极化下全向雷达散射截面（RCS)均值逐渐增大,垂直极化时减小。得到了两种飞行器目标处于瑞利区、谐振区时依靠外形隐身所能达到的RCS极限值。结果分析表明,在瑞利区和谐振区,目前的外形隐身措施存在不能超越的极限,在这两个区域的雷达隐身需结合外形和材料隐身技术。     

Signal Processors and Accuracy of Three-Beam Monopulse Tracking Radar

The problem of implementing a monopulse tracking radar is considered when three beams are used rather than the customary four. Signal processors are developed for both amplitude and phase comparison radar cases and the functional form is given for the general case (a combination or hybrid case). Accuracy is investigated by applying the Cramer-Rao inequality. General results are given for the maximum theoretical accuracy of estimating target amplitude, phase, and position angles when the radar is of the amplitude comparison type. Equations sufficient for obtaining accuracies in the phase comparison and combination cases are included.     

基于CAD二次开发的飞行器隐身性能计算方法

在飞行器同雷达对抗时的不同威胁情况下,分析了在雷达仰视照射下飞行器的隐身性能。通过绘制雷达仰角图,得到了目标飞行器在某典型雷达照射下的暴露与隐身区域,从而量化了目标飞行器的隐身性能。通过CATIA二次开发技术实现了CAD模型的便捷修改,为优化外形隐身特性提供支持。最后通过一个具体算例验证种方法的效果,并说明方法具有实用意义。