Dr. Yonghe Zhang Profile

Dr. Yonghe Zhang

at Innovation Academy for Microsatellites

SPIE Involvement:

Author

Publications (7)

Proceedings Article | 18 December 2023 Paper

Key techniques for accurate sensing and compensation of rotating imaging degradation information

Chengcheng Fan, Yonghe Zhang

Proceedings Volume 12963, 129630D (2023) https://doi.org/10.1117/12.3003932

KEYWORDS: Image processing, Satellites, Imaging systems, Modeling, Tunable filters, Remote sensing, Motion measurement, Motion models, Signal filtering, Motion estimation

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Optical remote sensing satellites are an important part of the current Earth observation technology, and with the development of space technology and the diversification of application requirements, their imaging models are becoming more and more diversified. The overall development trend of optical remote sensing satellites is to achieve ultra-large width and ultra-high spatial resolution. In the face of the growing demand for large-scale and high-timed Earth observation in the region, rotational geography has gradually become a new model and has been gradually studied and developed. The rotating ultra-large wide imaging optical satellite adopts the conical scanning earth observation technology system of area scan camera, realizes ultra-large area observation through conic scanning, and designs widearea search imaging and encryption imaging modes in key areas, which has the characteristics of wide-area, highresolution and multi-angle imaging. The degradation information of rotational imaging optical satellite images is difficult to accurately estimate and the spatiotemporal characteristics are complex, and the ground imaging process is composed of satellite flight motion and turntable rotation, and in order to compensate for the image shift effect in the imaging process, the satellite is equipped with a fast reflection compensation mirror and the detector rotation mechanism for realtime motion compensation, which makes it difficult to accurately construct and calculate the image degradation model. In order to accurately obtain the mechanism and process information of image quality degradation at the focal plane, the accurate perception and modeling method of dynamic imaging degradation information is studied, and key technologies such as progressive information fusion based on overall weighting of bidirectional filtering, separation and spatiotemporal modeling of high and low frequency degradation information based on Fourier model, and single-sided image compensation restoration based on degenerate spatiotemporal model are broken, and distortion-free high-quality images in rotational maneuvering mode are obtained, which lays a theoretical and algorithmic foundation for the design and data processing of rotating imaging optical satellites.

Proceedings Article | 1 December 2023 Paper

Control technology and verification of space advanced technology demonstration satellite

Jinsong Li, Yingquan Yang, Yonghe Zhang, Xiaofeng Zhang, Wen Chen, Heng Zhou

Proceedings Volume 12940, 1294008 (2023) https://doi.org/10.1117/12.3010650

KEYWORDS: Satellites, Control systems, Bismuth, Gyroscopes, Angular velocity, Information fusion, Aerospace engineering

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Proceedings Article | 27 November 2023 Poster + Paper

Key techniques for virtual imaging model construction and correction of rotating imaging satellite

Chengcheng Fan, Yonghe Zhang

Proceedings Volume 12766, 127660Y (2023) https://doi.org/10.1117/12.2687138

KEYWORDS: Image processing, Charge-coupled devices, Satellites, Satellite imaging, Image sensors, Imaging arrays, Motion models, Distortion, Cameras, Imaging systems

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According to different scenarios and needs, the rotating imaging optical satellite designs three task observation modes such as wide-area coverage, encrypted observation and regional video, the long edge of the camera field of view is placed radially along the turntable, the short edge of the field of view is placed tangentially, the camera pendulum axis is placed along the short side of the field of view, the pendulum mirror can be adjusted in three gears, the satellite adopts nadir pointing, that is, the rotation axis of the turntable is in the direction of the nadiel, the turntable maintains a normal working speed of 24 ° / s, rotates every 15s, and adjusts one gear per rotation of the camera pendulum mirror. After rotating 3 times in 50s, it can cover the range of 5~60° in the direction of nadir direction. The image obtained based on the above mode has rotation misalignment, different angles, abnormal speed imaging, integration time jump, and internal distortion in a single frame image. Therefore, how to perform sensor correction for multi-angle rotating images to achieve continuous, complete and distortion-free restoration is a key scientific problem to be solved in this paper. The purpose of optical satellite sensor correction is to design the imaging payload and imaging mode, realize seamless image stitching, eliminate image distortion caused by lens distortion, CCD distortion, integrated time jump, allospeed imaging and tremor disturbance, and finally obtain continuous, complete and distortion-free high-quality images. In order to obtain high-quality ultra-large wide format optical satellite images without distortion and seamless stitching, the construction and correction method of virtual imaging model for rotating area array mode is studied, and key technologies such as multi-gear virtual large area array CCD design and construction and virtual correction method based on ideal composite motion model are broken through to achieve distortion-free, seamless stitching and high-quality restoration compensation, providing comprehensive, accurate and rapid data and information support for subsequent on-orbit remote sensing applications.

Proceedings Article | 24 May 2023 Paper

Chlorophyll-a concentration inversion and distribution with GOCI images in the Changjiang Estuary

Dinghui shang, Chengcheng Fan, Yonghe Zhang, Xinping Wang

Proceedings Volume 12706, 127060S (2023) https://doi.org/10.1117/12.2682817

KEYWORDS: Reflectivity, Satellites, Water, Satellite imaging, Data modeling, Mathematical optimization, Earth observing sensors, Turbidity

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Proceedings Article | 31 August 2022 Poster + Paper

Scenario design and preliminary verification of SVOM operational test

Kun Chen, Ruifeng Su, Qingyun Mao, Junwang He, Binpin Su, Xingbo Han, Wen Chen, Xiaofeng Zhang, Dong Li, Yonghe Zhang, Fabienne Schaffhauser, Martine Jouret

Proceedings Volume 12181, 121815R (2022) https://doi.org/10.1117/12.2629750

KEYWORDS: Satellites, X-ray telescopes, Computer programming, Gamma-ray astronomy, Astronomical instrumentation

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