{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T00:31:27Z","timestamp":1760401887741,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,1,10]],"date-time":"2020-01-10T00:00:00Z","timestamp":1578614400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Scientific Research Fund Project of Xi\u2019an Aeronautical University","award":["2019KY0207"],"award-info":[{"award-number":["2019KY0207"]}]},{"name":"Shaanxi Provincial Key Research and Development Program","award":["2019GY-043"],"award-info":[{"award-number":["2019GY-043"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61501348 and 61801363"],"award-info":[{"award-number":["61501348 and 61801363"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"China Postdoctoral Science 210 Foundation","award":["2017M611912"],"award-info":[{"award-number":["2017M611912"]}]},{"DOI":"10.13039\/501100010242","name":"Jiangsu Planned Projects for Postdoctoral Research Funds","doi-asserted-by":"publisher","award":["1701059B"],"award-info":[{"award-number":["1701059B"]}],"id":[{"id":"10.13039\/501100010242","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013314","name":"111 Project","doi-asserted-by":"publisher","award":["B08038"],"award-info":[{"award-number":["B08038"]}],"id":[{"id":"10.13039\/501100013314","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004543","name":"China Scholarship Council","doi-asserted-by":"publisher","award":["20180696503"],"award-info":[{"award-number":["20180696503"]}],"id":[{"id":"10.13039\/501100004543","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Algorithms"],"abstract":"<jats:p>Signal-to-noise ratio (SNR) estimation is essential in the unmanned aerial vehicle (UAV) orthogonal frequency division multiplexing (OFDM) system for getting accurate channel estimation. In this paper, we propose a novel non-data-aided (NDA) SNR estimation method for UAV OFDM system to overcome the carrier interference caused by the frequency offset. First, an absolute value series is achieved which is based on the sampled received sequence, where each sampling point is validated by the data length apart. Second, by dividing absolute value series into the different series according to the total length of symbol, we obtain an output series by stacking each part. Third, the root mean squares of noise power and total power are estimated by utilizing the maximum and minimum platform in the characteristic curve of the output series after the wavelet denoising. Simulation results show that the proposed method performs better than other methods, especially in the low synchronization precision, and it has low computation complexity.<\/jats:p>","DOI":"10.3390\/a13010022","type":"journal-article","created":{"date-parts":[[2020,1,10]],"date-time":"2020-01-10T10:20:29Z","timestamp":1578651629000},"page":"22","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Non Data-Aided SNR Estimation for UAV OFDM Systems"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2898-8204","authenticated-orcid":false,"given":"Junfang","family":"Li","sequence":"first","affiliation":[{"name":"School of Electronic Engineering, Xi\u2019an Aeronautical University, Xi\u2019an 710077, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9872-9710","authenticated-orcid":false,"given":"Mingqian","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Integrated Service Networks, Xidian University, Xi\u2019an 710071, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ningjie","family":"Tang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Integrated Service Networks, Xidian University, Xi\u2019an 710071, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7966-0017","authenticated-orcid":false,"given":"Bodong","family":"Shang","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Wireless@Virginia Tech, Arlington, VA 24061, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2281","DOI":"10.1109\/TCOMM.2018.2792014","article-title":"Caching UAV assisted secure transmission in hyper-dense networks based on interference alignment","volume":"66","author":"Zhao","year":"2018","journal-title":"IEEE Trans. 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