雷达多目标回波模拟技术研究
发布时间：2019-03-03 17:47
【摘要】：现代技术发展日新月异,雷达研究周期越来越长,雷达工作环境也越来越复杂,研究一部新型雷达,需要进行大量的外场测试来验证其性能。现代雷达功能日益复杂和多样化,在设计和分析雷达过程中需要考虑大量的随机因素和非线性影响,另外在实际实验环境中,受制约的因素有很多,参数的离散性很大,有时为了测得一个较为准确的参数,需要反复进行多次实验,这样,所耗费的人力物力是非常巨大的,不仅增加了科研经费,也延误了科研的进度,这些因素对雷达的设计和测试等带来了很大的困难和不便。相对来说,采用雷达信号模拟的方式来设计、测试雷达,便有了很多的优点。雷达信号模拟技术主要研究目标特性模型,电磁环境干扰特性模型以及回波实时模拟。本文主要研究的是回波实时模拟技术。当需要实时模拟多个目标时,对硬件资源的要求比较高。本文给出了基于FPGA平台,可实时并行模拟4个目标的雷达回波模拟系统的方案,并介绍了测试方法和测试结果。本文首先根据雷达原理介绍了点目标雷达回波信号的基本模型,分析了线性调频信号的特点,详细的介绍了目标的起伏模型,并以Swerling IV型分布为例,讲述了产生随机数的方法,给出了含4个子阵元的相控阵天线方向图函数模型,介绍了如何实现和、差波束调制,分析了任意运动轨迹目标的运动模型。然后文章讲述了具体实现方法。对于天线方向图函数调制和目标起伏调制,方向图数据和目标起伏数据均采用上位机预先产生,下载到目标板再读取的方式。正余弦波形的产生采用了Cordic算法来实现,只需要简单的移位和加减法既可以实现任意频率的正余弦波形的产生。为了节省硬件资源,滤波器的采用了高效的多相结构。本文还详细介绍了如何实现对各个模块的控制,如何模拟多普勒调制、距离延迟及天线的扫描。在硬件实现之前,对整个模拟系统做了MATLAB仿真。最后介绍了基于FPGA的多目标回波模拟系统的测试方法,首先单独测试了各个模块的功能,然后系统联调测试,并且给出了相应的测试结果。本文的创新点在于克服了以往只是对单个目标的模拟,实现了对4个运动目标的并行实时回波模拟,并做了详细的分析,给出了一些高效的算法,节省了所需的硬件资源。
[Abstract]:With the rapid development of modern technology, the research period of radar becomes longer and longer, and the working environment of radar becomes more and more complex. To study a new type of radar, it is necessary to carry out a lot of external field tests to verify its performance. The function of modern radar is becoming more and more complex and diversified. In the process of radar design and analysis, a large number of random factors and nonlinear effects need to be considered. In addition, in the practical experimental environment, there are many restricted factors and the discreteness of parameters is very large. Sometimes, in order to measure a more accurate parameter, repeated experiments need to be carried out, so that the manpower and material resources spent are very huge, not only increasing the funding for scientific research, but also delaying the progress of scientific research. These factors bring great difficulty and inconvenience to radar design and test. Relatively speaking, using radar signal simulation to design, test radar, there are many advantages. Radar signal simulation technology mainly studies target characteristic model, electromagnetic environment interference characteristic model and echo real-time simulation. In this paper, the echo real-time simulation technology is mainly studied. When real-time simulation of multiple targets is needed, the requirements for hardware resources are high. In this paper, the scheme of radar echo simulation system based on FPGA platform and real-time parallel simulation of four targets is presented, and the testing methods and results are introduced. In this paper, the basic model of radar echo signal of point target is introduced according to the principle of radar, the characteristic of LFM signal is analyzed, the undulating model of target is introduced in detail, and the method of generating random number is described by taking the distribution of Swerling IV as an example. The pattern function model of phased array antenna with four sub-array elements is given, and how to realize sum and differential beam modulation is introduced, and the motion model of arbitrary trajectory target is analyzed. Then the article describes the concrete implementation method. For antenna pattern function modulation and target fluctuation modulation, the pattern data and target fluctuation data are pre-generated by the host computer and then downloaded to the target board. Cordic algorithm is used to generate sine and cosine waveforms. Only simple shift, addition and subtraction are needed to generate sine and cosine waveforms with arbitrary frequency. In order to save hardware resources, the filter adopts an efficient multi-phase structure. How to realize the control of each module, how to simulate Doppler modulation, range delay and antenna scanning are also introduced in detail. Before the hardware implementation, the whole simulation system is simulated with MATLAB. Finally, the testing method of the multi-target echo simulation system based on FPGA is introduced. First, the function of each module is tested separately, then the system debugging test is carried out, and the corresponding test results are given. The innovation of this paper is to overcome the previous simulation of a single target, realize the parallel real-time echo simulation of four moving targets, and make a detailed analysis, give some efficient algorithms, and save the required hardware resources.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN955
本文编号：2433955
[Abstract]:With the rapid development of modern technology, the research period of radar becomes longer and longer, and the working environment of radar becomes more and more complex. To study a new type of radar, it is necessary to carry out a lot of external field tests to verify its performance. The function of modern radar is becoming more and more complex and diversified. In the process of radar design and analysis, a large number of random factors and nonlinear effects need to be considered. In addition, in the practical experimental environment, there are many restricted factors and the discreteness of parameters is very large. Sometimes, in order to measure a more accurate parameter, repeated experiments need to be carried out, so that the manpower and material resources spent are very huge, not only increasing the funding for scientific research, but also delaying the progress of scientific research. These factors bring great difficulty and inconvenience to radar design and test. Relatively speaking, using radar signal simulation to design, test radar, there are many advantages. Radar signal simulation technology mainly studies target characteristic model, electromagnetic environment interference characteristic model and echo real-time simulation. In this paper, the echo real-time simulation technology is mainly studied. When real-time simulation of multiple targets is needed, the requirements for hardware resources are high. In this paper, the scheme of radar echo simulation system based on FPGA platform and real-time parallel simulation of four targets is presented, and the testing methods and results are introduced. In this paper, the basic model of radar echo signal of point target is introduced according to the principle of radar, the characteristic of LFM signal is analyzed, the undulating model of target is introduced in detail, and the method of generating random number is described by taking the distribution of Swerling IV as an example. The pattern function model of phased array antenna with four sub-array elements is given, and how to realize sum and differential beam modulation is introduced, and the motion model of arbitrary trajectory target is analyzed. Then the article describes the concrete implementation method. For antenna pattern function modulation and target fluctuation modulation, the pattern data and target fluctuation data are pre-generated by the host computer and then downloaded to the target board. Cordic algorithm is used to generate sine and cosine waveforms. Only simple shift, addition and subtraction are needed to generate sine and cosine waveforms with arbitrary frequency. In order to save hardware resources, the filter adopts an efficient multi-phase structure. How to realize the control of each module, how to simulate Doppler modulation, range delay and antenna scanning are also introduced in detail. Before the hardware implementation, the whole simulation system is simulated with MATLAB. Finally, the testing method of the multi-target echo simulation system based on FPGA is introduced. First, the function of each module is tested separately, then the system debugging test is carried out, and the corresponding test results are given. The innovation of this paper is to overcome the previous simulation of a single target, realize the parallel real-time echo simulation of four moving targets, and make a detailed analysis, give some efficient algorithms, and save the required hardware resources.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN955
【参考文献】
相关硕士学位论文 前1条
1 徐青;机载相控阵雷达多目标模拟技术研究[D];南京理工大学;2008年
，本文编号：2433955
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