基于双调频斜率波形的MIMO-SAR成像
发布时间：2018-10-24 19:50
【摘要】：多输入多输出(Multi-Input Multi-Output,MIMO)雷达作为一种新体制雷达技术,已受到国内外科研工作者的广泛关注。由于其综合利用阵列与分集技术,引入了远多于传统合成孔径雷达(Synthetic Aperture Radar,SAR)的等效观测通道和处理信号的自由度,可以有效解决传统SAR中高分辨率和宽测绘带之间的矛盾。然而,由于MIMO雷达多收发阵列的结构特点,传统的雷达成像算法不能被直接利用,同时发射波形彼此之间的相互干扰、MIMO雷达平台的等效相位中心误差、雷达的布阵方式都会对MIMO-SAR成像带来巨大的影响。针对这些问题,本文从MIMO-SAR的工作原理出发,分别对MIMO雷达的波形优化、波形加窗处理、MIMO的等效相位中心误差和多输入多输出的雷达阵列布阵方法等展开了深入的研究。同时根据发射波形的特点,对成像算法进行改进,并最终实现MIMO-SAR的高分辨率和宽测绘带成像。论文的主要工作包括:1.从MIMO雷达发射波形的正交性、多普勒敏感性等方面综合考虑,引入了一种双调频斜率波形的信号模型,并重点分析了该信号的互相关性、自相关性,以及多普勒特性。为提高该信号的脉冲压缩性能,对波形进行加窗优化设计。2.通过分析等效相位中心误差对MIMO雷达成像的影响,构建了等效相位中心的误差模型,并给出了相应的补偿方法。同时根据MIMO雷达多发多收阵列形式,对MIMO-SAR的收发阵列进行了优化配置。3.针对双调频斜率波形(Double Frequency Slope,DFS)波形的模型,对MIMO-SAR回波进行建模。重点分析了回波在距离多普勒域的特点,并推导了距离向的脉冲压缩函数和相位补偿函数,提出了一种基于双调频斜率波形在MIMO-SAR中的成像方案,并通过与正交频分复用线性调频信号的成像性能对比,突出了DFS波形在MIMO-SAR中的优势。4.针对远距离,宽场景和高分辨率下存在的距离徙动问题,提出了一种基于DFS波形的频率域校正距离弯曲的成像方法,并通过真实宽场景下的成像,验证了MIMO-SAR在解决高分辨率和宽测绘带之间矛盾的有效性。
[Abstract]:As a new system radar technology, multiple input multiple output (Multi-Input Multi-Output,MIMO) radar has been paid more and more attention by researchers at home and abroad. Because of its comprehensive use of array and diversity technology, the equivalent observation channel and the degree of freedom of signal processing, which are far more than traditional synthetic aperture radar (Synthetic Aperture Radar,SAR), can effectively solve the contradiction between high resolution and wide mapping band in traditional SAR. However, due to the structural characteristics of multi-transceiver array of MIMO radar, the traditional radar imaging algorithm can not be directly used, and at the same time, the mutual interference between the transmitted waveforms and the equivalent phase center error of the MIMO radar platform. Radar array will have a great impact on MIMO-SAR imaging. Based on the principle of MIMO-SAR, the waveform optimization, waveform windowing, equivalent phase center error of MIMO and multi-input and multi-output array of MIMO radar are studied in this paper. At the same time, according to the characteristics of the transmitting waveform, the imaging algorithm is improved, and finally the high resolution and wide mapping band imaging of MIMO-SAR is realized. The main work of the thesis includes: 1. Considering the orthogonality and Doppler sensitivity of MIMO radar transmitting waveform, a signal model of double frequency modulation slope waveform is introduced, and the cross-correlation, autocorrelation and Doppler characteristics of the signal are analyzed. In order to improve the pulse compression performance of the signal, the waveform is optimized with window. 2. By analyzing the effect of the equivalent phase center error on the MIMO radar imaging, the error model of the equivalent phase center is constructed, and the corresponding compensation method is given. At the same time, according to the MIMO radar multi-receiving array form, the MIMO-SAR transceiver array is optimized. 3. 3. Based on the model of double frequency modulation slope waveform (Double Frequency Slope,DFS), the MIMO-SAR echo is modeled. The characteristics of echo in range Doppler domain are analyzed emphatically, and the pulse compression function and phase compensation function in range direction are derived. An imaging scheme based on double frequency modulation slope waveform in MIMO-SAR is proposed. Compared with the imaging performance of orthogonal frequency division multiplexing (OFDM) LFM signal, the advantages of DFS waveform in MIMO-SAR are highlighted. 4. Aiming at the range migration problem in long range, wide scene and high resolution, a range bending correction method in frequency domain based on DFS waveform is proposed. The validity of MIMO-SAR in solving the contradiction between high resolution and wide mapping band is verified.
【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】：TN957.52
本文编号：2292386
[Abstract]:As a new system radar technology, multiple input multiple output (Multi-Input Multi-Output,MIMO) radar has been paid more and more attention by researchers at home and abroad. Because of its comprehensive use of array and diversity technology, the equivalent observation channel and the degree of freedom of signal processing, which are far more than traditional synthetic aperture radar (Synthetic Aperture Radar,SAR), can effectively solve the contradiction between high resolution and wide mapping band in traditional SAR. However, due to the structural characteristics of multi-transceiver array of MIMO radar, the traditional radar imaging algorithm can not be directly used, and at the same time, the mutual interference between the transmitted waveforms and the equivalent phase center error of the MIMO radar platform. Radar array will have a great impact on MIMO-SAR imaging. Based on the principle of MIMO-SAR, the waveform optimization, waveform windowing, equivalent phase center error of MIMO and multi-input and multi-output array of MIMO radar are studied in this paper. At the same time, according to the characteristics of the transmitting waveform, the imaging algorithm is improved, and finally the high resolution and wide mapping band imaging of MIMO-SAR is realized. The main work of the thesis includes: 1. Considering the orthogonality and Doppler sensitivity of MIMO radar transmitting waveform, a signal model of double frequency modulation slope waveform is introduced, and the cross-correlation, autocorrelation and Doppler characteristics of the signal are analyzed. In order to improve the pulse compression performance of the signal, the waveform is optimized with window. 2. By analyzing the effect of the equivalent phase center error on the MIMO radar imaging, the error model of the equivalent phase center is constructed, and the corresponding compensation method is given. At the same time, according to the MIMO radar multi-receiving array form, the MIMO-SAR transceiver array is optimized. 3. 3. Based on the model of double frequency modulation slope waveform (Double Frequency Slope,DFS), the MIMO-SAR echo is modeled. The characteristics of echo in range Doppler domain are analyzed emphatically, and the pulse compression function and phase compensation function in range direction are derived. An imaging scheme based on double frequency modulation slope waveform in MIMO-SAR is proposed. Compared with the imaging performance of orthogonal frequency division multiplexing (OFDM) LFM signal, the advantages of DFS waveform in MIMO-SAR are highlighted. 4. Aiming at the range migration problem in long range, wide scene and high resolution, a range bending correction method in frequency domain based on DFS waveform is proposed. The validity of MIMO-SAR in solving the contradiction between high resolution and wide mapping band is verified.
【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】：TN957.52
【参考文献】
相关期刊论文 前1条
1 张娟;张林让;刘楠;;MIMO雷达最大似然波达方向估计方法[J];系统工程与电子技术;2009年06期
，本文编号：2292386
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