{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:27:08Z","timestamp":1760146028815,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,23]],"date-time":"2024-09-23T00:00:00Z","timestamp":1727049600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key RD Program of China","award":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"],"award-info":[{"award-number":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"]}]},{"name":"National Natural Science Foundation of China","award":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"],"award-info":[{"award-number":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"]}]},{"name":"UK Engineering and Physical Sciences Research Council","award":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"],"award-info":[{"award-number":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"]}]},{"name":"Basic Research of National Institute of Metrology","award":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"],"award-info":[{"award-number":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"]}]},{"name":"Henan science and technology research","award":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"],"award-info":[{"award-number":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"]}]},{"name":"Haizhi project of Henan Association for science and technology","award":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"],"award-info":[{"award-number":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"]}]},{"name":"cultivation plan of young teachers of Henan University of Technology","award":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"],"award-info":[{"award-number":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"]}]},{"name":"innovation fund of Henan University of Technology","award":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"],"award-info":[{"award-number":["2023YFC2205603","U1804161","61901431","EPX0353521","EPY0009861","AKYJJ1906","222102210269","HZ202201","21420169","2021zkcj07"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The airborne distributed position and orientation system (ADPOS), which integrates multi-inertia measurement units (IMUs), a data-processing computer, and a Global Navigation Satellite System (GNSS), serves as a key sensor in new higher-resolution airborne remote sensing applications, such as array SAR and multi-node imaging loads. ADPOS can provide reliable, high-precision and high-frequency spatio-temporal reference information to realize multinode motion compensation with the various nonlinear filter estimation methods such as Central Difference Kalman Filtering (CDKF), and modified CDKF. Although these known nonlinear models demonstrate good performance, their noise estimation performance with its linear minimum variance estimation criterion is limited for ADPOS. For this reason, in this paper, Central Difference Variational Filtering (CDVF) based on the variational optimization process is presented. This method adopts the conjugate gradient algorithm to enhance the estimation performance for mean correction in the filtering update stage. On one hand, the proposed method achieves adaptability by estimating noise covariance through the variational optimization method. On the other hand, robustness is implemented under the minimum variance estimation criterion based on the conjugate gradient algorithm to suppress measurement noise. We conducted a real ADPOS flight test, and the experimental results show that the accuracy of the slave motion parameters has significantly improved compared to the current CDKF. Moreover, the compensation performance shows a clear enhancement.<\/jats:p>","DOI":"10.3390\/rs16183541","type":"journal-article","created":{"date-parts":[[2024,9,24]],"date-time":"2024-09-24T03:49:46Z","timestamp":1727149786000},"page":"3541","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Central Difference Variational Filtering Based on Conjugate Gradient Method for Distributed Imaging Application"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9769-9863","authenticated-orcid":false,"given":"Wen","family":"Ye","sequence":"first","affiliation":[{"name":"Division of Mechanics and Acoustics Metrology, National Institute of Metrology, Beijing 102200, China"}]},{"given":"Fubo","family":"Zhang","sequence":"additional","affiliation":[{"name":"Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China"}]},{"given":"Hongmei","family":"Chen","sequence":"additional","affiliation":[{"name":"Faculty of Electrical Engineering, Henan University of Technology, Zhengzhou 450001, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,23]]},"reference":[{"key":"ref_1","first-page":"5211509","article-title":"Enhanced Disturbance Suppression Method Based on Nonlinear H\u221e Filtering for Distributed POS in Aerial Earth Observation Imaging Application","volume":"60","author":"Wang","year":"2022","journal-title":"IEEE Trans. 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