大椭圆轨道SAR(Highly-Elliptic Earth Orbital SAR)作为低轨SAR(LEOSAR)、中高轨SAR(MEOSAR、HEOSAR)的结合,具有观测范围广、时间分辨率高的特点,是非常具有应用前景的新型SAR系统。本文根据大椭圆轨道SAR的系统特点及优势,对大椭圆轨...大椭圆轨道SAR(Highly-Elliptic Earth Orbital SAR)作为低轨SAR(LEOSAR)、中高轨SAR(MEOSAR、HEOSAR)的结合,具有观测范围广、时间分辨率高的特点,是非常具有应用前景的新型SAR系统。本文根据大椭圆轨道SAR的系统特点及优势,对大椭圆轨道SAR系统设计中的成像体制选择、工作参数选择、成像模式设计等进行了论述。针对大椭圆轨道SAR系统存在的特殊问题,对大椭圆轨道SAR的关键技术问题进行分析,提出了针对上升/下降时段、远地时段观测特点的高精度成像算法,并对大椭圆轨道SAR天线和空间环境适应性设计难点进行了总结。这些研究结果为大椭圆轨道SAR系统实现及应用提供有益参考。展开更多
The attractiveness of flying several SAR （synthetic aperture radar） satellites in a semi-active configuration has been proposed by several studies. The closest implementation of such a mission scenario is exemplifie...The attractiveness of flying several SAR （synthetic aperture radar） satellites in a semi-active configuration has been proposed by several studies. The closest implementation of such a mission scenario is exemplified by the current Terra SAR-X and Tandem-X mission, where both spacecraft are identical monostatic platforms capable of operating in various modes. The bistatic operation mode of the Tandem-X mission is a basic form of the semi-active multi-static operation mode where one satellite serves as a transmitter while the other records the scattered signals simultaneously. The use of a typical monostatic SAR spacecraft operating in-tandem with several receiver only spacecraft is a semi-active mode of operation. This paper examines the capabilities of implementing a constellation of S-band spaceborne SAR platform for alongtrack interferometry over the equatorial region for velocity measurement with particular focus on ship detection. The orbit for the mission is an inclined circular low Earth orbit, which ensures high revisit time, quick coverage and high data throughput. The pendulum configuration is adopted to maintain the relative distance between successive SAR platforms. The conditions and constraints necessary to achieve the orbit geometry required to conduct alongtrack interferometry are defined. The alongtrack separation between platforms necessary to measure specified ship velocity is also discussed. Finally an error budget estimate of the measure radial velocity is provided.展开更多
文摘大椭圆轨道SAR(Highly-Elliptic Earth Orbital SAR)作为低轨SAR(LEOSAR)、中高轨SAR(MEOSAR、HEOSAR)的结合,具有观测范围广、时间分辨率高的特点,是非常具有应用前景的新型SAR系统。本文根据大椭圆轨道SAR的系统特点及优势,对大椭圆轨道SAR系统设计中的成像体制选择、工作参数选择、成像模式设计等进行了论述。针对大椭圆轨道SAR系统存在的特殊问题,对大椭圆轨道SAR的关键技术问题进行分析,提出了针对上升/下降时段、远地时段观测特点的高精度成像算法,并对大椭圆轨道SAR天线和空间环境适应性设计难点进行了总结。这些研究结果为大椭圆轨道SAR系统实现及应用提供有益参考。
文摘The attractiveness of flying several SAR （synthetic aperture radar） satellites in a semi-active configuration has been proposed by several studies. The closest implementation of such a mission scenario is exemplified by the current Terra SAR-X and Tandem-X mission, where both spacecraft are identical monostatic platforms capable of operating in various modes. The bistatic operation mode of the Tandem-X mission is a basic form of the semi-active multi-static operation mode where one satellite serves as a transmitter while the other records the scattered signals simultaneously. The use of a typical monostatic SAR spacecraft operating in-tandem with several receiver only spacecraft is a semi-active mode of operation. This paper examines the capabilities of implementing a constellation of S-band spaceborne SAR platform for alongtrack interferometry over the equatorial region for velocity measurement with particular focus on ship detection. The orbit for the mission is an inclined circular low Earth orbit, which ensures high revisit time, quick coverage and high data throughput. The pendulum configuration is adopted to maintain the relative distance between successive SAR platforms. The conditions and constraints necessary to achieve the orbit geometry required to conduct alongtrack interferometry are defined. The alongtrack separation between platforms necessary to measure specified ship velocity is also discussed. Finally an error budget estimate of the measure radial velocity is provided.
