机动雷达大型天线自动对接技术的研究

机动雷达大型天线阵面常采用多块天线子阵面吊装拼接的架设方式,架设时受架设效率低、吊装操作存在不确定因素等的制约,使得大型雷达的机动性较差。通过对大型天线阵面自动对接技术的研究,将目前已有的室内大型零部件自动对接技术应用到大型天线装配技术中,以实现机动雷达大型天线的快速装配。主要论述了机动雷达大型天线自动对接的工程原理和所需攻克的关键技术,其中包括数字化自动测量技术、天线位姿自动调节技术和伺服控制技术等;并对其主要功能的实现方法进行了研究。     

某车载雷达的调平设计

本文以某车载相控阵制导雷达自动调平系统为引子,较为详细地探讨了车载雷达调平的设计方法。     

雷达载车调平支腿机械设计

机动雷达一般是通过自动调平系统实现雷达载车自动调平的。随着机动雷达的广泛应用,作为雷达载车自动调平系统的重要组成部分,调平支腿设计的成功与否会直接或间接地影响到雷达整机的工作性能。本文介绍了一种机电式自动调平系统的调平支腿的机械设计,其机械部分具有结构紧凑、可靠性高、维护简单等特点。     

雷达天线自动调平系统的设计与实现

雷达天线平台的水平度严重影响雷达的测量和跟踪精度，文中介绍了一种基于单片机和可编程逻辑器件（CPLD）的雷达天线平台自动调平系统，系统简单可靠，主要采用四条支撑腿联动方法，在最短时间内自动调平天线载车，并将天线平台倾斜度实时传送给雷达主机，从而大大地提高了雷达的测量和跟踪精度，以及雷达天线的架设和撤收速度。     

高机动性地面雷达的现状和未来发展趋势

本文主要叙述了高机动性地面雷达的现状、影响高机动性的因素,同时预测了高机动性地面雷达的未来发展趋势。     

赋形波束双弯曲反射面天线探讨

针对赋形波束双弯曲反射面天线出现条带相交情况以及用大口径天线直接在骨架筋条上铺设网来构成反射面，提出了反射面重新构造方法。消除了反射面上的奇异区域，解决了一般情况下赋形波束双弯曲反射面天线的设计问题，提高了设计精度。文中还给出了设计实例和计算测试结果。     

自动调平技术研究

自动调平系统主要用于雷达车、战车等车辆的自动调平,也可应用于其他地面设备的自动调平.机电式自动调平系统采用机械式4点支撑结构,调平时4条支腿自动伸缩调整载体至水平,保证调平后载体的水平和稳定;自动调平技术通过水平传感、调平控制将电气和机械融合成为一个有机的整体,使机电自动调平系统快速、平稳、准确、可靠,满足了高精度自动调平的需要.     

基于CAN总线的柔性平台调平控制系统设计

介绍了一种完全由CAN总线将控制、监测及驱动单元串接起来的弹性平台自动调平控制系统,充分地发挥了CAN总线的抗干扰、高可靠性的优点,并配以带有一定智能化的软件处理算法,很好地实现了雷达天线车高机动性和高精度调平的要求。系统结构紧凑、性能可靠、可操作性强而且日常维护、维修方便。     

一种雷达自动举升系统的设计

为获得雷达的高机动性,我们针对雷达的自动架设撤收要求,将液压传动系统应用于自动举升系统中。本文详细阐述和论证了一种液压系统的设计,并对其可靠性预测作了一些探讨。     

某雷达自动调平机构的设计分析

某雷达在作战前需要进行雷达车的架设调平工作，采用电动自动调平是一种快速可靠的调平方法。它同以往的手动，液压传动调平相比有许多优点：如调平时间短，调平精度高，可靠性高等。本文着重就调平机构的结构设计进行分析，探讨其系统的高效性和可靠性。     

Calibration of a polarimetric radar using a rotatable dihedralcorner reflector

Based on the existing mathematical formalisms of radar polarimetry, it is necessary to perform accurate and diversified polarimetric measurements in the real world to thoroughly investigate signature definition, identification, and classification of radar targets. For this study the Delft Atmospheric Research Radar (DARR) is used. This ground-based polarimetric FM-CW radar operates in the S-band. The purpose of the present paper is the polarimetric calibration of the DARR. Among the passive reflectors, a rotatable dihedral corner reflector is a suitable calibration object. It enables one to measure different scattering matrices with only one reflector. One alignment must be performed and the scattering matrices are measured at the same range. By measuring several scattering matrices, the accuracy of the calibration result can be estimated. A measurement campaign with a rotatable dihedral corner reflector was therefore performed. The experimental results and the calibration procedure are presented in this paper     

一种低成本的雷达诱饵辐射器

通过用表面电流法计算和实验发现:文中的2种圆锥形反射面天线可分别产生有效口径的半功率宽度较宽的、增益不低的扇形波束和针状波束;同时.较大的制造公差对2种圆锥形反射面天线的特性的影响不大.2种圆锥形反射面天线适合用作雷达诱饵辐射器,具有其他产生相同形状波束的天线所不具备的易于加工、成本极低的优点.     

Radar calibration by using frequency domain measurements

A calibration technique is described that uses a rotating corner reflector of known echoing area as a secondary calibration standard. Audio-frequency Doppler signals from the radar are recorded on a low-bandwidth magnetic-tape recorder. Offline frequency-domain analysis is then used to calibrate the radar in terms of absolute echoing area.     

Radar polarimeter measures orientation of calibration corner reflectors

We have analyzed radar polarimeter signals from a set of trihedral corner reflectors located in the Goldstone Dry Lake in Cafifornia, and observed three types of scattering behavior: i) Bragg-like slightly rough surface scattering that represents the background signal from the dry lake, ii) trihedral corner reflector scattering that returns the incident polarization, and iii) two-bounce corner reflector scattering resulting from a particular alignment of a trihedral reflector. In the latter case, we can measure within about 3° the orientation angle of the apparent dihedral trough, even though the 2-m reflector is much smaller than the 10-m resolution element of our radar. Thus a radar calibration approach using trihedral corner reflectors should be designed such that precise alignment of the reflectors is ensured, as three-bounce and two-bounce geometries lead to very different cross sections and hence very different inferred calibration factors.     

Application of rectangular and elliptical dielcore feed horns toelliptical reflector antennas

The pattern characteristics of elliptical reflector antennas are investigated when they are fed by rectangular and elliptical horns partially filled with a dielectric. The bandwidth characteristics of these dielcore horns are superior to those of their corrugated horn counterparts. Representative reflector patterns are computed to properly demonstrate the utility of these feeds for reflector antennas with elliptical apertures. This reflector antenna exhibits high efficiency and low cross polarization, and may be suitable for radar and satellite antenna applications. The antenna configuration may become useful in relatively small antennas where more than 10% cross-polar bandwidth is required. The efficient dielcore horns may also be used as feeds for elliptical nonshaped dual-reflector antennas     

Synthetic aperture radar calibration using reference reflectors

A simple expression for the terrain backscatter coefficient is derived in terms of the integrated power of an adjacent known radar reflector in a synthetic aperture radar (SAR) image. It is shown that this technique for SAR image calibration is independent of the radar system focus or partial coherence and thereby possesses an important advantage over the usual technique, which relies on an estimate of the peak of the reflector impulse response. Results from airborne SAR overflights of corner reflectors and active radar calibrators are used to demonstrate the validity and consistency of the method and to show that the method is robust under defocus caused by an incorrect FM rate or inadequate motion compensation of data collected during turbulence. It is also shown that the fading errors associated with the integral method are comparable to or slightly worse than those associated with the peak estimation method. However, this small disadvantage is outweighed by the fact that the integral method is independent of actual resolution     

基于极化分解的舰船和角反射器鉴别方法

使用角反射器是舰船电子对抗中常用的一种无源干扰方式,它在时域、频域和空域上与舰船的雷达回波都没有显著差异,因此传统单极化雷达很难有效鉴别舰船和角反射器。分析了舰船和角反射器在极化回波上的特性差异,并基于Krogager极化分解提取了单频点和多频点情况下的特征矢量,通过支持矢量机对舰船和角反射器进行了鉴别。电磁计算数据表明：该方法可以较好地对二者进行鉴别,且对单角反射器和阵列角反射器都有效,为解决舰船和角反射器的鉴别问题提供了一个可行的思路。     

A two-frequency radar for vehicle automatic lateral control

The use of a side-looking radar in conjunction with a sidewall reflector is one means of obtaining lateral position information for use in vehicle automatic lateral control. The principle of operation of a two-frequency radar for such use is presented along with a discussion of the reflector design and construction difficulties. Some results of the full-scale testing of this radar using two different types of reflecting surfaces are included. The performance of this radar system is compared with that of the highly accurate wire follower. In general, tracking errors on the order of twice those obtained with the wire follower were achieved. It appears that with some redesign of the radar, performance equal to or better than that of the wire follower should eventually result.     

Depolarizing trihedral corner reflectors for radar navigation andremote sensing

A conventional trihedral corner reflector can be modified to present either a twist-polarizing or a circularly polarizing response by adding conducting fins of rectangular corrugations of prescribed dimensions and orientation to one of its interior surfaces. Since the modified reflector retains most of the mechanical ruggedness and ease of manufacture of the original, it is suitable for deployment in the field for extended periods as required in radar navigation and remote sensing applications. For most directions of incidence the response of the reflector is dominated by triple-bounce reflections from the interior and is a function of the size and shape of the reflecting panels, the dimensions of the corrugations, and the orientation of the reflector with respect to the radar. Experimental results show that prototype twist-polarizing and circularly polarizing reflectors respond as predicted     

雷达信标综合测试仪方案研究

利用现代仿真技术和数字信号处理技术、数字储频技术（DRFM），文章提出了一种雷达调试综合测试仪器的设计方案。该综合测试仪器在雷达维修过程，能够完成对校光电轴、校距离、测改善因子、测雷达灵敏度、抗干扰性能等各项指标测试，同时对测试场地没有严格的要求，所以使得在部队现有的装备下，很容易完成对这些项目的测试。这是一台价格低，性能优异的专用雷达信标综合性能测试仪。