雷达

Luneberg lens is a spherical lens which its permittivity varies with normalized radial coordinates. It is fabricated by using different homogeneous dielectric centrically layered media. The lens can focus a parallel beam of rays from any direction exactly at a point on the surface. If it is made by adding a reflecting surface "metallic cap", it is called Luneberg lens reflector. It can reflect incident wave into plane wave in incoming direction. It is usually applied in antenna, radar reflector,satellite-based, and mobile-communucation.

龙伯球透镜为一种介电系数与半径成一固定比例的球形透镜，大部分是由数层不同介电系数介电质组合而成，而其主要特性能够把入射波聚焦到球表面一点，假使在透镜表面处镀上一圆锥角金属层即为龙伯球透镜反射器，能把入射波依平面波的型态反射回原入射端，通常用於天线、雷达、卫星通讯、军事等方面。

ABSTRACT A systematic introduction about the background of both the radar target identification and the high-resolution parametric estimation techniques is presented in this dissertation firstly.

本文首先系统介绍了国内外学术界关于雷达目标识别和基于累量的高分辨参数估计方法的研究现状。

This paper introduces a kind of new method based on expression parsing which has been used in radar automation test system.

本文论述了一种使用表达式解析的故障诊断方法，并将其用于某型雷达系统的故障诊断保障系统中。

All above laid a foundation for the research of polarimetric information processing and application. Then, target optimum polarization and polarimetric synthesis technique were studied. By constraining polarimetric states of transmitting and receiving antennas, co-polarized and cross-polarized signatures were obtained. Because the received wave was partially polarized, completely polarized, completely unpolarized, and total available power signatures were defined based on the power of the return wave.

接着，论文深入研究了目标最佳极化和极化合成技术，通过约束收发天线的极化状态可以得到共极化特征图和交叉极化特征图，由于雷达接收的电磁波通常是部分极化的，根据接收波的平均功率密度可以得到未极化特征图、完全极化特征图和匹配极化特征图，在极化特征图空间中搜索可以很容易地获得目标的最佳极化，这些目标最佳极化可以作为极化目标识别和分类的极化特征。

The research of soil quality is becoming the focused topic of the international pedology. Ground Penetrating Radar as a quick,unintrusive and economic method is accepted by the scholars home and abroad.

探地雷达作为一种快速、无损、经济的土壤质量检测方法，正在被国内外学者所接受，然而由于土壤的复杂性，使得这一技术在具体应用时还存在一些问题。

Actively involved in optical stereo mapping satellites, interference radar satellites, laser-ranging satellites, mapping satellite data such as applied research, and gradually perfect the emergency mapping equipment, to enhance quick access to geographic information and processing capabilities.

积极参与光学立体测图卫星、干涉雷达卫星、激光测距卫星、测绘卫星数据等应用研究，逐步完善应急测绘装备，增强地理信息快速获取及处理的能力。

This paper analysized the relationship between sampling frequency fs and the taps N of low pass filter in A/D transform and got a formula expression, which can give reference to the parameter design of quadrature sampling.; aiming at the wave distortion in traditional arithmetic of quadrature sampling with pulse compression, an improved algorithm has been studied and validated in Matlab and get perfecter result. In order to enlarge the detect distance of Radar, a method of part pulse compression is put forward, the realistic sense and the implement scheme is analysized.

本文分析了在正交插值前端A/D变换中采样率的选择与正交插值低通滤波器的阶数的关系，得到公式化的表达式，可为正交采样参数设计提供参考；针对传统的正交插值及脉冲压缩算法中的波形畸变提出了改进方案，并通过仿真实验得到较好的效果；为扩大雷达的探测距离，提出部分脉压的方案，详细分析了其理论意义及实现方法。

At last experimental data of radar targets are used to test the performance of the method.

最后利用雷达目标测量数据进行了目标识别的实验。

In the radar elevation coordinate, the multipath effects are more severe, which cause periodic peak error in the target height measurement.

在雷达俯仰角方向上多径误差的影响尤为严重，使得目标高度的测量误差表现为周期性的尖峰误差。

At last,simulation research is carried out on radar echo of two same frequency vibration scatter points.Theoretical annlysis and simulation result indicate that the model is effective and that the periodicity of amplitude modulation function and phase modulation function is invariable as the number of scatter points increased,but,their amplitudes are variational.

最后对两个同频振动散射点合成雷达回波进行了计算机仿真研究，理论分析和仿真结果表明，该模型是有效的，并且随着同频振动散射点数的增加，其幅度调制函数和相位调制函数的周期性不发生变化，只是它们的值会随着振动点数的增加而改变。

They go to town. Would you just ask them?

他们在城里你能问他们吗？

Ossein pretreated for a2 weeks period exhibited the maximum% yield incase of bone gelatin, while the yield from intact skin was higher than that realized incase of de-scaled skin.

预处理时间达2星期的骨胶原表现出最高的骨明胶百分产量，然而从未处理鱼皮中得到的产率比去鳞的鱼皮得到的要高。