{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T18:59:31Z","timestamp":1771959571345,"version":"3.50.1"},"reference-count":36,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,4,30]],"date-time":"2024-04-30T00:00:00Z","timestamp":1714435200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62301042"],"award-info":[{"award-number":["62301042"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["3050012222315"],"award-info":[{"award-number":["3050012222315"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Fundamental Research Funds for the Central Universities","award":["62301042"],"award-info":[{"award-number":["62301042"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["3050012222315"],"award-info":[{"award-number":["3050012222315"]}]},{"name":"Beijing Institute of Technology, and funds of National Key Lab of Microwave Imaging Technology","award":["62301042"],"award-info":[{"award-number":["62301042"]}]},{"name":"Beijing Institute of Technology, and funds of National Key Lab of Microwave Imaging Technology","award":["3050012222315"],"award-info":[{"award-number":["3050012222315"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Mini\u2013unmanned aerial vehicles (mini-UAVs) are emerging as a promising platform for through-wall radar to sense the enclosed space in cities, especially high-rise buildings, due to their excellent maneuverability. However, due to unavoidable environmental interference such as airflow, mini-UAVs are prone to trajectory deviation thus degrading their sensing accuracy. Most of the existing approaches model the impact of trajectory deviation into a polynomial phase error on the received signal, which cannot fit the space-variant motion error well. Moreover, the large trajectory deviations of UAVs introduce the unavoidable envelope error. This article proposes an autofocusing algorithm based on the back projection (BP) image, which directly estimates the trajectory deviations between the actual and measured track. Thus, the problem of the 2D space variability of the motion error can be circumvented. The proposed method mainly consists of two steps. First, we estimate the trajectory deviation in the line-of-sight (LOS) direction by exploring the underlying linear property of the wall embedded in the BP imaging result. Then, the estimated trajectory deviation in the LOS direction is compensated for to obtain an updated BP image, followed by a Particle Swarm Optimization (PSO) approach to estimate the trajectory deviation along the track through focusing targets behind the wall. Simulations and practical experiments show that the proposed algorithm can accurately estimate the serious trajectory deviations larger than the range resolution, improving the sensing robustness of UAV-borne through-wall radar greatly.<\/jats:p>","DOI":"10.3390\/rs16091593","type":"journal-article","created":{"date-parts":[[2024,4,30]],"date-time":"2024-04-30T08:14:31Z","timestamp":1714464871000},"page":"1593","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Trajectory Deviation Estimation Method for UAV-Borne Through-Wall Radar"],"prefix":"10.3390","volume":"16","author":[{"given":"Luying","family":"Chen","sequence":"first","affiliation":[{"name":"School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314019, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5772-8137","authenticated-orcid":false,"given":"Xiaolu","family":"Zeng","sequence":"additional","affiliation":[{"name":"School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314019, China"}]},{"given":"Shichao","family":"Zhong","sequence":"additional","affiliation":[{"name":"School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314019, China"}]},{"given":"Junbo","family":"Gong","sequence":"additional","affiliation":[{"name":"Beijing Institute of Technology Chongqing Innovation Center, Chongqing 401120, China"}]},{"given":"Xiaopeng","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314019, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Chaves, C.S., Geschke, R.H., Shargorodskyy, M., Brauns, R., Herschel, R., and Krebs, C. 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