地面合成孔径雷达系统中的数据采集与控制

【作者】 王浩；

【导师】 盛卫星；

【作者基本信息】 南京理工大学 ， 通信与信息系统， 2008， 硕士

【摘要】 合成孔径雷达(Synthetic Aperture Radar),简称SAR,指的是雷达移动、被成像的目标固定不动的运动成像方式。它用小口径天线收发宽带微波信号,通过在空间分集的办法合成一个大的天线口径,从而得到高的纵向和横向分辨率。作为主动雷达,SAR具有不受光照、天气条件影响的特点,可以全天候、全天时对地观测,还可以透过地表和植被获取信息。本文以科研项目为背景,围绕地面合成孔径雷达成像系统的研制,开展了以下几个方面的研究工作:(1)参与设计和完成了合成孔径微波成像实验系统一套。该实验系统工作于X波段,使用阶跃调频连续波体制实现距离维的高分辨,采用在导轨上依靠电动机精确平移的合成孔径实现方位向高分辨,系统距离和方位分辨率小于0.5米,可对外场全尺寸目标进行二维成像。(2)设计和完成了该实验系统中的系统控制卡和数据采集卡,两块板卡互相协调配合,较好的完成了数据采集,运动控制,频率控制等工作。(3)对连续波雷达载波泄漏问题做了探讨,对各种连续波体制雷述载波泄漏有源对消方法进行了理论分析。通过实验的办法得到了较好的效果,系统性能得到了很大的提高。更多还原

【Abstract】 Synthetic aperture radar, SAR for short, means the imaging pattern of radar moving and target by imaging put. It uses small aperture antenna transmitting and receiving wide-band microwave signal, and synthesizes large antenna aperture by special diversity which can gain high range and cross-range resolution. As initiative radar, SAR has the characteristics of immune to illumination and weather changing, which can all weather and all time observe and gain information penetrate through the earth’s surface and vegetation. This dissertation, based on scientific research item, is focused on the ground SAR system. The main contributions are as follows,(1)Join in designing and implementing a set of synthetic aperture microwave imaging system in X band with stepped frequency continuous wave to realize high range resolution and high azimuth resolution based on synthetic large aperture by system moving on track. The imaging system can be applied to the imaging of outdoor full-size target.(2)Design and implement a system controlling card and a data collecting card in the system. The two card assort with each other and successful finish a lot of work such as: data collecting, locomotion controlling, frequency controlling and so on.(3) In this paper, the problem of carrier feed-through in continuous wave system which limits the detection range of the radar system is analyzed in detail. The active method of feed-through nulling in continuous wave radar systems is investigated theoretically . By experiment, we get better result and system performance.更多还原