The interference technology is one of the focuses of radar imaging increasingly . not only does it provide some additional information of target recognition and detection , but also has it other applications to three - dimension imaging , scaling and moving target detection and so on . and the baseline is one of the keys of the interferometer system 同样建立在成像技术上的干涉技术日益成为雷达成像中的焦点，它不仅为目标识别和检测提供了辅助信息，并能实现简单成像不能完成的诸如三维成像、定标、动目标检测等功能，而基线则为干涉系统的关键。
( 1 ) . here we build the system space geometry model : the transmitter and receiver fly on different platforms and at different height , two flight paths are unparallel . based on the chirp signal and the taylor series , we analyze the range history and synthetic aperture time , then demonstrate the equation of the azimuth resolution about air - born bistatic spotlight synthetic aperture radar , meanwhile we obtain the equations of doppler bandwidth and doppler frequency modulate rate 本文以机载聚束式合成孔径雷达成像作为研究背景,主要完成了以下几方面的工作: ( 1 )建立了一种机载双站聚束式sar空间几何数学模型,对方位分辨力进行了理论分析,进行了数值分析与仿真,讨论了不同条件对双站聚束模式sar系统分辨力的影响。
Synthetic aperture radar ( sar ) is a kind of new imaging radar . high - resolution radar image can be obtained by using sar under all weather , day and night and long distance conditions . it is a branch of radar technology and a research emphasis , so it has high value in military and civil applications 合成孔径雷达( sar )是二战后发展起来的一种新的雷达技术，具有全天候、全天时、远距离、高分辨成像的能力，是雷达成像技术的一个重要分支，也是雷达领域的研究热点，在军事和民用方面都有重要的应用价值。
For the effect of motion of target , a method of isar motion compensation based on scattering center tracking is used . for the difficulty of getting echo signal of bistatic isar of moving target , a method of simulating moving target using turntable data is used . finally the imaging results by using simulating data based on scattering center tracking show the effectiveness of the methods 针对目标的运动对双站逆合成孔径雷达成像质量的影响,运用基于散射重心跟踪的isar运动补偿方法来消除目标运动对成像质量的影响,并针对双站isar运动目标回波获取的困难,运用一种用转台数据模拟运动目标回波的方法来获得仿真数据,最后用仿真数据验证了基于散射重心跟踪法的双站isar运动补偿的正确性。
The main work is given as follows : the stepped - frequency waveform synthesizing the wideband signal , the synthetic range profile ( srp ) by ifft , the range resolution of stepped - frequency waveform , the effect of the radial velocity on the srp , the radial velocity compensation , ambiguity function , waveform design and stepped frequency sar imaging and so on 包括：频率步进波形合成超宽带信号分析， ifft方法获得目标一维距离像与距离分辨率分析，径向速度对目标距离像的影响、速度补偿、频率步进信号的模糊函数分析，以及频率步进波形照射下的合成孔径雷达成像、波形设计与系统设计。
The far - distance targets can be detected with the aid of the satellite image and the ample respond time of the defensive system can be provided ; the cryptic cruise missile and anti - radiation cruise missile can be effectively detected and tracked recur to the infrared image . radar is widely used in the cruise missile defensive system . the radar in the sky can detect the further flying cruise missile , ground based radar and coastal defense radar can track and help weapons system aim at the oncoming force cruise missile 在目前情况下，卫星图像、红外图像以及雷达成像在探测、跟踪、识别、打击巡航导弹目标方面具有相当大的优势，借助于卫星图像可以在远距离发现目标，能够为防御系统提供比较充足的响应时间；借助于红外图像可以有效对付隐身巡航导弹和反辐射巡航导弹；雷达是在巡航导弹防御系统中使用最多的设备，空基雷达能够探测离防区比较远的巡航导弹，陆基雷达和海基雷达能够跟踪巡航导弹，并可协助武器系统瞄准来袭巡航导弹，尤其是雷达阵在巡航导弹防御中更是可以发挥重要作用。
In this paper , the main problem is to detect the position and velocity of moving target by fractional fourier transform which could be concluded by three parts , the echo model establishment of moving target , the realization of fractional fourier transform and parameters estimation of moving target , detailed contents are as follows . firstly , the paper analyses the echo model of sar static target and introduces a kind of sar imaging algorithm , range - doppler ( r - d ) algorithm 本文的主要内容包括三个部分,即动目标回波模型建立、分数阶傅立叶变换的实现和动目标参数估计,具体来说,其内容如下:首先,本文研究分析了合成孔径雷达静止点目标的回波模型并介绍了一种基本的合成孔径雷达成像算法? ?距离-多普勒( r - d )算法。
The above waveforms discussed are to synthesize the wb or uwb with narrow band pulses . assuming the transmitting uwb linear frequency modulation ( chirp ) , dechirp processing is introduced , and the method involved to obtain high resolution by reducing the if bandwidth is presented . furthermore , dechirp processing used to sar imaging is discussed , and the processing steps are described < wp = 4 >以上研究的两种信号形式都是通过窄带子脉冲串相参合成的方法来获得超宽带回波信号，本文还探讨了去斜率（ dechirp或stretch ）方法，分析了去斜率降低接收机中频带宽、 fft获得目标一维距离像的原理，并探讨了线性调频去斜率合成孔径雷达成像，给出了具体实现步骤。
By studying the present sar algorithm , analyzing the motion status of the plane and considering the requirement of the real - time processing , we improve the range - doppler algorithm to suit the real - time processing of the airborne sar imaging . the algorithm derived from the range - doppler algorithm has a simple structure and can compensate the plane ' s nonlinear motion and suit to real - time processing . the real - time processing experiments of the airborne sar imaging test the algorithm efficiency 本文通过对现有的合成孔径雷达成像算法的研究，以及对飞机运动状态的分析，针对实时处理的要求，对距离多普勒算法稍加改进，使之适合于机载合成孔径雷达成像实时处理使用，该算法根源于距离?多普勒算法，结构简单，既能够对飞机的不规则运动进行有效的补偿，又适合于实时处理。
In recent years , with the rapid development of the millimeter - wave radar technology and the demand of the safety , anticollision radar system is being studied and used widely . the if ( intermediate frequency ) circuit and the digital signal processing are two important parts of it 随着毫米波雷达技术的日益成熟和人们对安全性的迫切需要，近年来，防撞雷达系统得到了深入研究和广泛应用，如自动巡航控制、碰撞报警和防碰撞系统以及有待发展的雷达成像和汽车的自动驾驶系统等。
