{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:45:25Z","timestamp":1760147125850,"version":"build-2065373602"},"reference-count":44,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,12]],"date-time":"2023-01-12T00:00:00Z","timestamp":1673481600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>To address the weakness that the difference co-array (DCA) only enhances the degrees of freedom (DOFs) to a limited extent, a new configuration called the generalized nested array via difference\u2013sum co-array (GNA-DSCA) is proposed for direction of arrival (DOA) estimation. We consider both the temporal and spatial information of the array output to construct the DSCA model, based on which the DCA and sum co-array (SCA) of the GNA are systematically analyzed. The closed-form expression of the DOFs for the GNA-DSCA is derived under the determined dilation factors. The optimal results show that the GNA-DSCA has a more flexible configuration and more DOFs than the GNA-DCA. Moreover, the larger dilation factors yield significantly wider virtual aperture, which indicates that it is more attractive than the reported DSCA-based sparse arrays. Finally, a hole-filling strategy based on atomic norm minimization (ANM) is utilized to overcome the degradation of the estimation performance due to the non-uniform virtual array, thus achieving accurate DOA estimation. The simulation results verify the superiority of the proposed configuration in terms of virtual array properties and estimation performance.<\/jats:p>","DOI":"10.3390\/s23020906","type":"journal-article","created":{"date-parts":[[2023,1,13]],"date-time":"2023-01-13T02:57:33Z","timestamp":1673578653000},"page":"906","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Direction of Arrival Estimation of Generalized Nested Array via Difference\u2013Sum Co-Array"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7328-4815","authenticated-orcid":false,"given":"Yule","family":"Zhang","sequence":"first","affiliation":[{"name":"Graduate College, Air Force Engineering University, Xi\u2019an 710051, China"},{"name":"Air and Missile Defense College, Air Force Engineering University, Xi\u2019an 710051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7939-4588","authenticated-orcid":false,"given":"Guoping","family":"Hu","sequence":"additional","affiliation":[{"name":"Air and Missile Defense College, Air Force Engineering University, Xi\u2019an 710051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5284-7321","authenticated-orcid":false,"given":"Hao","family":"Zhou","sequence":"additional","affiliation":[{"name":"Air and Missile Defense College, Air Force Engineering University, Xi\u2019an 710051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juan","family":"Bai","sequence":"additional","affiliation":[{"name":"Air and Missile Defense College, Air Force Engineering University, Xi\u2019an 710051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chenghong","family":"Zhan","sequence":"additional","affiliation":[{"name":"Graduate College, Air Force Engineering University, Xi\u2019an 710051, China"},{"name":"Air and Missile Defense College, Air Force Engineering University, Xi\u2019an 710051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shuhan","family":"Guo","sequence":"additional","affiliation":[{"name":"Graduate College, Air Force Engineering University, Xi\u2019an 710051, China"},{"name":"Air and Missile Defense College, Air Force Engineering University, Xi\u2019an 710051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"108117","DOI":"10.1016\/j.sigpro.2021.108117","article-title":"Closed-form estimation algorithm for EMVS-MIMO radar with arbitrary sensor geometry","volume":"186","author":"Wen","year":"2021","journal-title":"Signal Process."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"108406","DOI":"10.1016\/j.sigpro.2021.108406","article-title":"Generalized spatial smoothing in bistatic EMVS-MIMO radar","volume":"193","author":"Wen","year":"2022","journal-title":"Signal Process."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2905","DOI":"10.3390\/rs14122905","article-title":"PARAFAC Estimators for Coherent Targets in EMVS-MIMO Radar with Arbitrary Geometry","volume":"14","author":"Zhang","year":"2022","journal-title":"Remote Sens."},{"key":"ref_4","unstructured":"Li, J., Li, P., Li, P., Tang, L., Zhang, X., and Wu, Q. 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