一种用于月面着陆的知识辅助单脉冲前视成像方法
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摘要
针对月面着陆过程中可能存在的着陆器倾斜而导致的结构损坏甚至颠覆等问题,提出了一种用于月面着陆的基于知识辅助的单脉冲前视成像方法。首先结合月面着陆器平台搭载的双通道雷达进行了理想情况下的单脉冲成像分析,然后分析了影响单脉冲成像性能的内在机理,并对雷达接收通道的不一致性进行了建模。在此基础上,将单脉冲成像问题转化为通道相位误差估计问题;结合天线方向图的先验信息,通过对实际天线方向图与理想方向图数据信息的对比,利用最小二乘方法估计出两者之间的相位差异,并求得改进的单脉冲测角曲线。最后对接收到的回波数据进行相位补偿,就可以获得高分辨的月面着陆区域单脉冲成像结果。地球机载实测数据处理结果表明此方法可以获得高分辨的前视成像结果,可应用在月面着陆过程中。
To solve the problem of structure damage or overturn caused by lander's slant landing,an efficient knowledge aided monopulse forward-looking imaging algorithm for lunar landing was put forward. First,the ideal monopulse imaging method based on two-channel radar was analyzed. Then the reason for poor azimuth performance was analyzed and the channel error model was constructed.On this basis,the problem of monopulse imaging was converted into the problem of channel phase estimation. The least square( LS) method was utilized to estimate the phase error by exploiting the real antenna pattern information and a modified monopulse curve( MPC) was obtained. In the end,the high resolution lunar landing terrain was achieved with the modified MPC after phase compensation. Real data demonstrated that high azimuth resolution forward-looking image could be acquired by the proposed algorithm. It can be used in lunar landing.
To solve the problem of structure damage or overturn caused by lander's slant landing,an efficient knowledge aided monopulse forward-looking imaging algorithm for lunar landing was put forward. First,the ideal monopulse imaging method based on two-channel radar was analyzed. Then the reason for poor azimuth performance was analyzed and the channel error model was constructed.On this basis,the problem of monopulse imaging was converted into the problem of channel phase estimation. The least square( LS) method was utilized to estimate the phase error by exploiting the real antenna pattern information and a modified monopulse curve( MPC) was obtained. In the end,the high resolution lunar landing terrain was achieved with the modified MPC after phase compensation. Real data demonstrated that high azimuth resolution forward-looking image could be acquired by the proposed algorithm. It can be used in lunar landing.
引文
[1] Andrew E J,Allan R K,James B C,et al. Lidar-based haz-ard avoidance for safe landing on mars[J]. Journal of Guid-ance,Control,and Dynamics,2002,25(6):1091-1099.
[2] Chirold D E,Edward A R,David K R. Helicopter field tes-ting of NASA’s Autonomous Landing and Hazard AvoidanceTechnology(ALHAT)system fully integrated with the mor-pheus vertical test bed avionics[R]. JSC-CN-29275,NASAJohnson Space Center,2014.
[3]王海涛,马建华.基于降落图像的安全着陆点选择技术研究[J].航天返回与遥感,2012,33(4):13-18.Wang H T,Ma J H. Safe landing site selection based on land-ing image[J]. Spacecraft Recovery&Remote Sensing,2012,33(4):13-18.(in Chinese)
[4] Apollo program summary report[R]. JSC-09423,1975.
[5] Allan R K. Apollo guidance,navigation and control[R]. MITE-2411,1976.
[6]欧阳自远.我国月球探测的总体科学目标与发展战略[J].地球科学进展,2004(3):7-14.Ouyang Z Y. Scientific objectives of Chinese lunar explorationproject and development strategy[J]. Advance in Earth Sci-ences,2004(3):7-14.(in Chinese)
[7]李济生,航天器轨道确定[M].北京:国防工业出版社,2003:255-258.Li J S. Spacecraft Orbit Determination[M]. Beijing:NationalDefense Industry Press,2003:255-258.(in Chinese)
[8]陈金宝,聂宏,汪岸柳,等.月球软着陆系统关键技术研究与发展综述[J].中国机械工程,2006,S2:426-428.Chen J B,Nie H,Wang A L,et al. Development of soft land-ing for lunar lander[J]. China Mechanical Engineering,2006,S2:426-428.(in Chinese)
[9]张洪华,梁俊,黄翔宇,等.嫦娥三号自主避障软着陆控制技术[J].中国科学:技术科学,2014,44(6):559-568.Zhang H H,Liang J,Huang X Y,et al. Autonomous haz-ard avoidance control for Chang'e-3 soft landing[J]. ScienceChina:Technology Science,2014,44(6):559-568.(inChinese)
[10] Andres Huertas,Yang C. Passive imaging based on multicuehazard detection for spacecraft safe landing[R]. NTRS20060044143,2006.
[11] Horn B K P. Obtaining Shape From Shading Information,thePsychology of Computer Vision[M]. Mc Graw Hill,1975:115-155.
[12]丁萌,曹云峰,吴庆宪.月球探测器着陆中基于被动图像的着陆场搜索及斜坡估计[J].宇航学报,2009,30(6):2258-2264.Ding M,Cao Y F,Wu Q X. Passive image-based safe landingsite searching and slope estimation in probe landing[J]. Jour-nal of Astronautics,2009,30(6):2258-2264.(in Chinese)
[13]吴伟仁,王大轶,毛晓艳,等.基于月面单幅图像的软着陆障碍识别与安全区选取方法[J].深空探测学报,2014,1(4):262-268.Wu W R,Wang D Y,Mao X Y,et al. Obstacle recognitionand safe area selection method in soft landing based on singlelunar image[J].Journal of Deep Space Exploration,2014,1(4):262-268.(in Chinese)
[14]田林,戚发轫,果琳丽,等.载人月面着陆地形障碍探测与规避方案研究[J].航天返回与遥感,2014,36(6):11-19.Tian L,Qi F R,Guo L L,et al. Study of terrain hazard detec-tion and avoidance scheme for human lunar landing[J].Spacecraft Recovery&Remote Sensing,2014,36(6):11-19.(in Chinese)
[15] Richards M A. Fundamentals of Radar Signal Processing[M]. New York:Mc Graw-Hill,2005:385-401.
[16]吴迪,杨成杰,朱岱寅,等.一种用于单脉冲成像的自聚焦算法[J],电子学报,2016,44(8):1962-1968.Wu D,Yang C J,Zhu D Y,et al. An autofocusing algorithmfor monopulse imaging[J].Acta Electronic Sinica,2016,44(8):1962-1968.(in Chinese)
[2] Chirold D E,Edward A R,David K R. Helicopter field tes-ting of NASA’s Autonomous Landing and Hazard AvoidanceTechnology(ALHAT)system fully integrated with the mor-pheus vertical test bed avionics[R]. JSC-CN-29275,NASAJohnson Space Center,2014.
[3]王海涛,马建华.基于降落图像的安全着陆点选择技术研究[J].航天返回与遥感,2012,33(4):13-18.Wang H T,Ma J H. Safe landing site selection based on land-ing image[J]. Spacecraft Recovery&Remote Sensing,2012,33(4):13-18.(in Chinese)
[4] Apollo program summary report[R]. JSC-09423,1975.
[5] Allan R K. Apollo guidance,navigation and control[R]. MITE-2411,1976.
[6]欧阳自远.我国月球探测的总体科学目标与发展战略[J].地球科学进展,2004(3):7-14.Ouyang Z Y. Scientific objectives of Chinese lunar explorationproject and development strategy[J]. Advance in Earth Sci-ences,2004(3):7-14.(in Chinese)
[7]李济生,航天器轨道确定[M].北京:国防工业出版社,2003:255-258.Li J S. Spacecraft Orbit Determination[M]. Beijing:NationalDefense Industry Press,2003:255-258.(in Chinese)
[8]陈金宝,聂宏,汪岸柳,等.月球软着陆系统关键技术研究与发展综述[J].中国机械工程,2006,S2:426-428.Chen J B,Nie H,Wang A L,et al. Development of soft land-ing for lunar lander[J]. China Mechanical Engineering,2006,S2:426-428.(in Chinese)
[9]张洪华,梁俊,黄翔宇,等.嫦娥三号自主避障软着陆控制技术[J].中国科学:技术科学,2014,44(6):559-568.Zhang H H,Liang J,Huang X Y,et al. Autonomous haz-ard avoidance control for Chang'e-3 soft landing[J]. ScienceChina:Technology Science,2014,44(6):559-568.(inChinese)
[10] Andres Huertas,Yang C. Passive imaging based on multicuehazard detection for spacecraft safe landing[R]. NTRS20060044143,2006.
[11] Horn B K P. Obtaining Shape From Shading Information,thePsychology of Computer Vision[M]. Mc Graw Hill,1975:115-155.
[12]丁萌,曹云峰,吴庆宪.月球探测器着陆中基于被动图像的着陆场搜索及斜坡估计[J].宇航学报,2009,30(6):2258-2264.Ding M,Cao Y F,Wu Q X. Passive image-based safe landingsite searching and slope estimation in probe landing[J]. Jour-nal of Astronautics,2009,30(6):2258-2264.(in Chinese)
[13]吴伟仁,王大轶,毛晓艳,等.基于月面单幅图像的软着陆障碍识别与安全区选取方法[J].深空探测学报,2014,1(4):262-268.Wu W R,Wang D Y,Mao X Y,et al. Obstacle recognitionand safe area selection method in soft landing based on singlelunar image[J].Journal of Deep Space Exploration,2014,1(4):262-268.(in Chinese)
[14]田林,戚发轫,果琳丽,等.载人月面着陆地形障碍探测与规避方案研究[J].航天返回与遥感,2014,36(6):11-19.Tian L,Qi F R,Guo L L,et al. Study of terrain hazard detec-tion and avoidance scheme for human lunar landing[J].Spacecraft Recovery&Remote Sensing,2014,36(6):11-19.(in Chinese)
[15] Richards M A. Fundamentals of Radar Signal Processing[M]. New York:Mc Graw-Hill,2005:385-401.
[16]吴迪,杨成杰,朱岱寅,等.一种用于单脉冲成像的自聚焦算法[J],电子学报,2016,44(8):1962-1968.Wu D,Yang C J,Zhu D Y,et al. An autofocusing algorithmfor monopulse imaging[J].Acta Electronic Sinica,2016,44(8):1962-1968.(in Chinese)