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1.
Polish radar research and development since 1953 is reviewed, covering the development and production of surveillance radars, height finders, tracking radars, air traffic control (ATC) radars and systems, and marine and Doppler radars. Some current work, including an L-band ATC radar for enroute control, a weather channel for primary surveillance radar, signal detection in non-Gaussian clutter, adaptive MTI filters and postdetection filtering, and a basic approach to radar polarimetry, is examined.<>  相似文献   

2.
This work describes the application of the extended Kalman filter (EKF) to the estimation of range and bearing biases in marine radars by performing a map-matching between the data from hydrographic charts and the radar images. By defining at least two corresponding points from the radar image and the electronic charts, the technique provides a rapid and accurate calibration in range and bearing, giving also estimates for the speed, heading, latitude, and longitude of the ship. The method is tested with simulated data to check convergence and later with real data obtained from a navigation console installed on a patrol boat The technique does not require GPS nor speed information from the ship log unit, however it is shown that their inclusion can improve the estimation.  相似文献   

3.
张洪海  汤一文  许炎 《航空学报》2020,41(7):323844-323844
持续增长的交通需求量和日趋饱和的可用空域资源促使未来空中交通管理向基于航迹运行(TBO)的精细化管理模式转变。在TBO概念的基础上,依据目前繁忙机场终端区常见进场航线结构,提出了对应TBO模式下的截点直飞方式与融合点方式进场交通流优化模型,并以法国戴高乐机场终端区为例,构建了仿真运行环境。基于实际飞行计划与雷达记录轨迹模拟生成了航空器四维航迹,而后运用上述2种模型对进场交通流进行了优化,根据仿真结果对特定交通流参数展开了对比分析。研究结果表明,模型可通过航迹选择、时隙分配、顺序交换及动态间隔等方式有效化解终端区内潜在的航空器冲突并保持交通流安全高效运行,同时在一定程度上揭示了TBO模式下交通流的部分运行特性,为以四维航迹为核心的未来空中交通管理策略提供了理论支持。  相似文献   

4.
基于傅里叶变换的航迹对准关联算法   总被引:7,自引:2,他引:5  
何友  宋强  熊伟 《航空学报》2010,31(2):356-362
研究了在组网雷达存在系统误差情况下的目标航迹关联问题,理论分析了雷达系统误差对目标航迹的影响,并将该影响表示为目标航迹的旋转和平移量。在此基础上,提出了一种基于傅里叶变换的系统误差配准前航迹对准关联算法,该算法将组网雷达的航迹数据看做为一种整体信息,采用傅里叶变换理论来估计和补偿组网雷达目标航迹数据到融合中心航迹数据的相对旋转量和平移量,将雷达网中雷达上报的目标航迹数据对准到融合中心,从而不依赖于估计雷达网系统误差,实现了误差配准前的航迹准确关联,能够为后端的系统误差配准提供可靠的关联目标航迹数据。  相似文献   

5.
Modern radar design has benefited from the evolution of specialized digital processing, allowing high resolution ground mapping, target identification, and target tracking under many conditions. Air-to-air interception makes use of complex decision processes to select from many modes that depend on the clutter backgrounds and flight profiles. Today's multimode radars provide this information for each task while minimizing distractions. Fire control radars support a wide selection of weapons, including cannons and guided missiles. This is possible because of advanced digital processing. In the interval since WW II, radar design evolved from vacuum tubes to semiconductors and then to massively integrated circuits. Computers specialized for fast Fourier transforms (FFTs) have revolutionized radar data processing. System reliability has improved from a few hours to hundreds of hours. Effective built-in test informs ground maintenance personnel of problems for easy maintenance and low failure rates reduce or eliminate field maintenance benches at forward locations. Airborne surveillance radars, such as AW ACS Joint Stars have changed the nature of warfare. Commanders have virtually full view of enemy and friendly forces. Radars, in combination with other remote sensors, provide precise weapon delivery, reducing collateral damage and making all weapons more effective  相似文献   

6.
Thirty eight radar experts contribute to this edition, which includes six completely new chapters on the following topics: ground penetrating radar; remote sensing with radar on satellites; multifunctional radar systems for fighter aircraft (MFAR); digital signal processing for radar; civil marine radar; and propagation. Each chapter contains references, ranging from 10 to 197, with a median of 71. The index runs 18 pages printed in double columns, but is not necessarily complete. Some topics, such as MIMO radar and long range radars to track satellites and ballistic missiles, will have to wait for a 4th edition. This text is the most authoritative, broadest, and deepest single volume on radar. The emphasis is on real world performance and real hardware that has been tested and works successfully in the real world, and the physics relevant to radar systems, as well as radar system engineering cost tradeoffs.  相似文献   

7.
MIMO radar: snake oil or good idea?   总被引:2,自引:0,他引:2  
MIMO communication is theoretically superior to conventional communication under certain conditions, and MIMO communication also appears to be practical and cost-effective in the real world for some applications. It is natural to suppose that the same is true for MIMO radar, but the situation is not so clear. Researchers claim many advantages of MIMO radar relative to phased array radars (e.g., better detection performance, better angular resolution, better angular measurement accuracy, improved robustness against RFI, ECM, multipath, etc.). We will evaluate such assertions from a system engineering viewpoint. In particular, there are serious trade-offs of MIMO vs. phased array radars relative to cost, system complexity, and risk considering numerous real world effects that are not included in most theoretical analyses. Moreover, in many cases one can achieve essentially the same radar system improvement with phased array radars using simpler, less expensive, and less risky algorithms. We evaluate roughly a dozen asserted advantages of MIMO radar relative to phased arrays.  相似文献   

8.
The history of development of automotive radars in different countries since 1972 is described using a short comparison of radar types. The authors indicate the planning of introduction of car radars in the near future according to information supplied by car companies. The purpose of the development of an automotive radar was to test different signal processing procedures both for distance and Doppler evaluation and also for a digital wavefront reconstruction to find out the angle position of a target. The block diagram, the main properties, the technical data of the radar system, the used antennas and the multiplexing of transmitting antennas is described. Finally some experimental results have been obtained under real traffic conditions  相似文献   

9.
This paper describes the development of a high-power, coherent radar system at W-band and discusses potential applications of radars with this new capability. Previous radars in this frequency band were limited by available power-amplifier technology to about 500 W of average power; WARLOC radar represents an increase in power, by 20 times, over previous coherent radars at 94 GHz. This performance improvement is possible due to the development of a gyroklystron amplifier specifically for this and future radars in this frequency band. The gyroklystron amplifier tubes deliver 100 kW peak power and 10 kW of average power at a center frequency of approximately 94 GHz. Other novel features of this radar include the use of highly overmoded waveguides and rotary joints for the transmission of power from the final power amplifier (FPA) to the antenna, and a high-power quasi-optical duplexer. The system uses a relatively large 1.8 m diameter (580-wavelength) Cassegrain antenna, which required the development of an antenna with an rms surface accuracy of 0.0025 in, to obtain long-range detection and identification of small objects. Test data show an antenna gain of 62.5 dB, confirming that the needed surface accuracy was achieved. Two mobile shelters house the radar system, permitting relocation to various test sites. WARLOC is presently operational at the Naval Research Laboratory's Chesapeake Bay Detachment facility, Maryland. It is being employed in radar imaging of airborne and surface objects, and in the scientific study of propagation effects and atmospheric physics phenomena.  相似文献   

10.
11.
Millimeter wavelength radars are used to study plasma effects associated with ionized flow fields of projectiles launched at hypersonic speeds into a free-flight ballistic range. Two CW Doppler radars, at frequencies of 35 and 70 Gc/s, measure the nose-on backscattering radar cross sections during flight. The design and performance of the two radars are described in detail. A signal simulator provides absolute calibration. The purpose is to measure changes that occur in the radar cross sections of hypersonic projectiles caused by highly ionized flow fields. Under certain conditions the nose-on backscattering radar cross section of a blunt-nosed metal projectile decreases drastically when a thin, shock-produced layer of ionized gas covers the projectile. A theoretical analysis of this effect is given. Comparisons between theoretical predictions and experimental data show good correlation.  相似文献   

12.
The ELDORA/ASTRAIA airborne Doppler weather radar was recently placed in service by US and French atmospheric sciences research laboratories. The ELDORA/ASTRAIA radar is designed to provide high resolution measurements of the air motion and rainfall characteristics of atmospheric storms which are too large, remote or fast-moving to be adequately observed by ground-based radars. This paper discusses the measurement requirements and the design goals of the radar and presents sample measurements from a recent weather research field program  相似文献   

13.
雷达组网中由于系统误差存在,航迹不能正确关联,因而无法进行有效的误差配准。为了解决这一问题,理论分析了系统误差对目标航迹的影响并将该影响表示为目标航迹的旋转和平移量,结合图像信号时频域特性,提出了一种基于归一化互相关的误差配准算法。该算法采用归一化互相关来估计和补偿组网雷达目标航迹到融合中心航迹的相对旋转参数和平移参数,从而为后面的系统误差配准提供可靠的航迹关联数据。  相似文献   

14.
The FIREFINDER Position Analysis System, FFPAS, provides FIREFINDER siting and operating personnel with a powerful tool. By automating the site selection and radar set-up processes, the FFPAS will significantly reduce the time and effort required to deploy FIREFINDER radars. Also, many radar effects that are difficult to include when calculations are performed manually, such as blind ranges and Doppler frequencies, variations in the target's radar cross sectional area (RCS), and the strength of the clutter return along a trajectory, can now be included in the radar siting and operational analyses. These capabilities will help the Army's FIREFINDER radars perform with maximum effectiveness on the modern battlefield  相似文献   

15.
季节 《航空学报》1981,2(1):87-94
 本文总结机载雷达中单脉冲技术的研究和应用,着重讨论幅度比较系统的关键技术,给出有关数据。 机载雷达中的单脉冲技术着眼于抗干扰性能和特殊应用。这些应用包括空对地测距、角分辨力改进、地形防撞。本文阐述了这些特殊应用。  相似文献   

16.
Air surveillance radars for this decade will be required to provide reliable target location and trajectory information in height as well as the conventional geographical coordinates. These threedimensional radars will perform this task in spite of adverse environmental conditions such as ground, airborne clutter, and electromagnetic interference. The use of powerful false-alarm control processing allows automatic target detection and remoting of target information without overloading central processing capabilities. The technological evolution of the past decade has allowed sophisticated analysis, antenna/receiver/transmitter design, and signal/data processing techniques to be applied to the next generation of practical production radar systems. These radars will meet more severe performance requirements and will be significantly improved in terms of reliability, maintainability, and life cycle cost considerations. A candidate radar to fulfill the air surveillance role of this decade is the Series 320 radar manufactured by ITT Gilfillan.  相似文献   

17.
Numerical simulation of RCS for carrier electronic warfare airplanes   总被引:3,自引:0,他引:3  
This paper studies the radar cross section(RCS) of carrier electronic warfare airplanes.Under the typical naval operations section, the mathematical model of the radar wave’s pitch angle incidence range analysis is established. Based on the CATIA software, considering dynamic deflections of duck wing leading edge flaps, flaperons, horizontal tail, and rudder, as well as aircraft with air-to-air missile, anti-radiation missile, electronic jamming pod, and other weapons, the 3D models of carrier electronic warfare airplanes Model A and Model B with weapons were established. Based on the physical optics method and the equivalent electromagnetic flow method, by the use of the RCSAnsys software, the characteristics of carrier electronic warfare airplanes’ RCS under steady and dynamic flights were simulated under the UHF, X, and S radar bands. This paper researches the detection probability of aircraft by radars under the condition of electronic warfare, and completes the mathematical statistical analysis of the simulation results. The results show that: The Model A of carrier electronic warfare airplane is better than Model B on stealth performance and on discover probability by radar detection effectively.  相似文献   

18.
当机载/弹载雷达工作在前视状态时,由于成像场景内不同角度处目标的多普勒差异很小,很难得到 高的角度分辨率。针对海面舰船目标的前视成像应用,利用成像区域具有明显稀疏性的特点,提出一种基于复 近似消息传递压缩感知处理的前视成像角度分辨率增强算法,建立前视成像的线性观测信号模型,给出复近似 消息传递的迭代计算过程,以及多通道雷达前视成像的处理流程。通过仿真数据和 X 波段雷达实测数据的处 理结果验证了该方法的有效性。  相似文献   

19.
隋东  邢娅萍  涂诗晨 《航空学报》2021,42(2):324300-324300
针对恶劣天气条件下可用空域资源不足导致的航班大面积延误问题,基于复杂网络修复理论和交通流分配理论,借鉴交通网络设计思想提出了一种航路网络修复优化策略。首先,建立了航路网络修复场景,基于气象信息生成了恶劣天气飞行受限区。然后,建立了上层模型以修复成本最低为目标函数、下层模型为多约束交通流分配模型的双层规划修复模型,应用改进粒子群算法对模型整体进行求解,结合K最短路径算法对下层模型进行求解。最后,提出局部和全局两类指标对航路网络修复效果进行评估。基于典型航路网络,以两类基础修复策略为对比方法,同时对比了实际运行结果,研究了不同修复策略的修复效果和适用性。仿真结果表明:航路网络修复优化策略既能弥补原有拓扑结构修复策略的结构受限不足,又能解决拓扑结构调整修复策略带来的巨额协调费用问题,能够保证在对正常运行航班干扰最小的同时,以最小的修复成本使所有受影响的航班都恢复正常运行,对于减缓航路拥堵和航班延误有极大的意义。  相似文献   

20.
Monopulse Radars Excited by Gaussian Signals   总被引:1,自引:0,他引:1  
This paper presents the theoretical probability densities of the outputs of both an amplitude-comparison monopulse radar and a phase-comparison monopulse radar when the monopulse radars are excited by Gaussian signals plus Gaussian noises. These probability densities are useful for studying the responses of monopulse radars to noise excitations. For example: Noise excitations arise when the monopulse radars are ?viewing? a noise source or a radar target consisting of randomly moving scatterers. The probability densities also serve as useful approximations for characterizing the outputs of monopulse radars when sinusoidal signals plus Gaussian noises excite the monopulse radars. Some special cases of the probability densities are presented in graphs.  相似文献   

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