雷达信号分析及半实物仿真系统研究

发布时间：2018-05-04 01:12

本文选题：FMICW + 距离模糊　；参考：《哈尔滨工业大学》2017年硕士论文

【摘要】：高频地波雷达需要设定信号参数去满足各种战术指标,对于远距离电离层回波折叠干扰问题需要保证选择的信号体制具有较大的不模糊距离。调频断续波是高频地波雷达的一种信号形式,能解决雷达系统收发隔离问题,但是由于受矩形脉冲的截断其常规信号处理会带来目标距离模糊;对于远距离回波混叠问题,调频断续波如果仅仅通过增大脉冲重复周期会带来发射平均功率的损失,影响雷达系统的作用距离。所以我们需要针对调频断续波自身特点和外部战场环境选择合适的处理手段和波形设计方法解决目前的问题。对于波形设计和算法的性能,传统的验证手段具有周期长、成本高等缺点,研究雷达信号处理的半实物仿真系统,有助于快速验证算法的有效性。下面是本文的主要研究内容:本文首先从调频断续波信号入手,给出了基于均匀脉冲截断线性调频信号的公式,研究了雷达目标信息提取的理论方法,并得出了FMICW信号体制下常规信号处理带来距离模糊现象的结论,然后进一步分析研究了解决距离模糊的方法,最后研究了测距范围和时域测距模糊的概念。而后主要研究了基于信号设计的FMICW信号抗远距离回波混叠问题。给出了雷达系统参数设置的基本要求,然后根据正交编码的特点,研究相位编码信号回波信号处理的基本理论。FMICW信号通过叠加正交编码,解决了抗远距离回波混叠问题,进一步研究分析了基于优化算法的正交编码设计。之后主要研究雷达信号模拟系统软件平台的设计和实现,从软件系统的总体设计到各个模块的流程设计来确定软件平台的框架,软件系统以C#和MATLAB混合编程实现信号波形编辑和信号的下载,通过SCPI以及.API接口函数实现波形验证和信号的采集。最后研究了各个硬件模块的性能指标和功能,从雷达波形合成技术和雷达信号产生技术出发完成了半实物仿真系统硬件平台的搭建,然后将系统软件控制平台和基于通用仪表的硬件平台结合起来从而验证了波形的正确性,处理采集到的真实信号验证了基于波形设计的FMICW信号抗远距离回波混叠算法具有较好的效果。搭建了基于System Vue的半实物仿真测试平台来为雷达系统测试提供更先进的手段。
[Abstract]:High frequency ground wave radar needs to set signal parameters to meet various tactical targets and to ensure that the selected signal system has a large unambiguous distance for the remote ionospheric echo folding interference problem. Frequency modulation intermittent wave is a signal form of high frequency ground wave radar, which can solve the problem of receiving and receiving isolation of radar system. However, because of the truncation of rectangular pulse, the conventional signal processing will bring the target distance ambiguity. If the frequency modulation intermittent wave only increases the pulse repetition period, it will bring about the loss of the average transmitting power and affect the range of the radar system. Therefore, we need to select appropriate processing methods and waveform design methods to solve the current problems according to the characteristics of frequency modulation intermittent waves and the external battlefield environment. For waveform design and algorithm performance, the traditional verification method has the disadvantages of long period and high cost. It is helpful to study the hardware-in-the-loop simulation system for radar signal processing to quickly verify the effectiveness of the algorithm. The following is the main content of this paper: firstly, the formula of linear frequency modulation signal based on uniform pulse truncation is given, and the theoretical method of radar target information extraction is studied. The conclusion of range ambiguity brought by conventional signal processing in FMICW signal system is obtained. Then, the methods to solve range ambiguity are analyzed and studied. Finally, the concepts of ranging range and time domain ranging ambiguity are studied. Then, the FMICW signal based on signal design is studied to resist long range echo aliasing. The basic requirements of radar system parameter setting are given. According to the characteristics of orthogonal coding, the basic theory of phase coded signal echo signal processing. FMICW signal is superposed by orthogonal coding to solve the problem of anti-long-range echo aliasing. The orthogonal coding design based on optimization algorithm is further studied and analyzed. Then it mainly studies the design and implementation of the software platform of radar signal simulation system, from the overall design of the software system to the flow design of each module to determine the framework of the software platform. The software system uses mixed programming of C # and MATLAB to realize signal waveform editing and signal downloading. Waveform verification and signal acquisition are realized by SCPI and .API interface function. Finally, the performance index and function of each hardware module are studied. The hardware platform of the hardware-in-the-loop simulation system is built from the radar waveform synthesis technology and radar signal generation technology. Then the system software control platform and the hardware platform based on universal instrument are combined to verify the correctness of the waveform. The processing of the collected real signal verifies that the FMICW signal anti-long-range echo aliasing algorithm based on waveform design has a good effect. The hardware-in-the-loop simulation test platform based on System Vue is built to provide more advanced means for radar system test.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN957.51

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