{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,9]],"date-time":"2025-12-09T08:28:06Z","timestamp":1765268886860,"version":"build-2065373602"},"reference-count":50,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,5,8]],"date-time":"2023-05-08T00:00:00Z","timestamp":1683504000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Natural Science Foundation of China","award":["62101402","61931016","62071344","2022TD-38","2021TQ0261","2021M702547","SAST2022-041"],"award-info":[{"award-number":["62101402","61931016","62071344","2022TD-38","2021TQ0261","2021M702547","SAST2022-041"]}]},{"name":"the Science and Technology Innovation Team of Shaanxi Province","award":["62101402","61931016","62071344","2022TD-38","2021TQ0261","2021M702547","SAST2022-041"],"award-info":[{"award-number":["62101402","61931016","62071344","2022TD-38","2021TQ0261","2021M702547","SAST2022-041"]}]},{"name":"the China Postdoctoral Science Foundation","award":["62101402","61931016","62071344","2022TD-38","2021TQ0261","2021M702547","SAST2022-041"],"award-info":[{"award-number":["62101402","61931016","62071344","2022TD-38","2021TQ0261","2021M702547","SAST2022-041"]}]},{"name":"the SAST Innovation fund","award":["62101402","61931016","62071344","2022TD-38","2021TQ0261","2021M702547","SAST2022-041"],"award-info":[{"award-number":["62101402","61931016","62071344","2022TD-38","2021TQ0261","2021M702547","SAST2022-041"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>To achieve high-resolution and wide-swath (HRWS) synthetic aperture radar (SAR) images, this paper focuses on resolving the problem of separating range-ambiguous echoes with the space\u2013time coding (STC) array. At the modeling stage, the transmit elements and pulses of the STC array are configured with time delay and phase coding modulation, which introduces extra degrees of freedom (DOFs) in the transmit domain. To separate the echoes corresponding to different range-ambiguity regions, the equivalent transmit beamforming is performed in the two-dimensional space\u2013frequency domain. Moreover, in order to compensate for the loss of range resolution during the beamforming progress, the frequency splicing method is proposed. At the analysis stage, the distributed target simulation is provided to demonstrate the effectiveness of obtaining HRWS SAR images in the STC radar. Additionally, the performance of resolving range ambiguity is compared with the traditional radar in terms of the range-ambiguity-to-signal ratio (RASR).<\/jats:p>","DOI":"10.3390\/rs15092465","type":"journal-article","created":{"date-parts":[[2023,5,8]],"date-time":"2023-05-08T03:00:28Z","timestamp":1683514828000},"page":"2465","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["High-Resolution and Wide-Swath SAR Imaging with Space\u2013Time Coding Array"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1581-8684","authenticated-orcid":false,"given":"Kun","family":"Yu","sequence":"first","affiliation":[{"name":"National Key Laboratory of Radar Signal Processing, Xidian University, Xi\u2019an 710071, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3119-4472","authenticated-orcid":false,"given":"Shengqi","family":"Zhu","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Radar Signal Processing, Xidian University, Xi\u2019an 710071, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9398-1308","authenticated-orcid":false,"given":"Lan","family":"Lan","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Radar Signal Processing, Xidian University, Xi\u2019an 710071, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6910-0195","authenticated-orcid":false,"given":"Biao","family":"Yang","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Radar Signal Processing, Xidian University, Xi\u2019an 710071, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1109\/MGRS.2022.3218801","article-title":"Sparse Synthetic Aperture Radar Imaging from Compressed Sensing and Machine Learning: Theories, Applications and Trends","volume":"10","author":"Xu","year":"2022","journal-title":"IEEE Geosci. 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