{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T13:22:22Z","timestamp":1770729742421,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2024,12,17]],"date-time":"2024-12-17T00:00:00Z","timestamp":1734393600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100018542","name":"Natural Science Foundation of Sichuan Province","doi-asserted-by":"publisher","award":["2024NSFSC0841"],"award-info":[{"award-number":["2024NSFSC0841"]}],"id":[{"id":"10.13039\/501100018542","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100018542","name":"Natural Science Foundation of Sichuan Province","doi-asserted-by":"publisher","award":["23ZDXM23"],"award-info":[{"award-number":["23ZDXM23"]}],"id":[{"id":"10.13039\/501100018542","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Soft Science Project of China Meteorological Administration","award":["2024NSFSC0841"],"award-info":[{"award-number":["2024NSFSC0841"]}]},{"name":"Soft Science Project of China Meteorological Administration","award":["23ZDXM23"],"award-info":[{"award-number":["23ZDXM23"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In the field of modern navigation and positioning, the ground-based eLoran system, serves as a vital backup to the global navigation satellite system (GNSS), which is crucial for numerous key applications. Signal demodulation, integral to eLoran\u2019s precision timing and information transmission, significantly affects system performance. Aiming at the pulse position modulation (PPM) characteristics of eLoran signals, this paper introduces an innovative phase spectrum smoothing demodulation (PSSD) algorithm, crafted to improve demodulation performance under complex noisy and interference-laden conditions. Following a systematic review of existing demodulation techniques in eLoran, this paper details the theoretical foundation, key steps, and significant impact of parameter selection for the PSSD algorithm. Then, the unique advantages in dealing with noise, continuous wave, and skywave interference are analyzed and verified. Through extensive experimental validation under various SNR and interference conditions, the PSSD algorithm shows significant superiority in demodulation performance compared with the traditional envelope phase detection (EPD) algorithm. The effectiveness of the PSSD algorithm in interference mitigation and its stable performance across diverse conditions confirm its potential to meet the high-precision timing requirements of eLoran systems, contributing to the advancement of modern communication systems.<\/jats:p>","DOI":"10.3390\/rs16244700","type":"journal-article","created":{"date-parts":[[2024,12,17]],"date-time":"2024-12-17T03:46:02Z","timestamp":1734407162000},"page":"4700","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Phase Spectrum Smoothing Demodulation: A New Frontier in eLoran Signal Processing for Enhanced Performance"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4996-712X","authenticated-orcid":false,"given":"Shiyao","family":"Liu","sequence":"first","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"Key Laboratory of Precise Positioning and Timing Technology, Chinese Academy of Sciences, Xi\u2019an 710600, China"}]},{"given":"Baorong","family":"Yan","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"Key Laboratory of Precise Positioning and Timing Technology, Chinese Academy of Sciences, Xi\u2019an 710600, China"}]},{"given":"Yu","family":"Hua","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"Key Laboratory of Precise Positioning and Timing Technology, Chinese Academy of Sciences, Xi\u2019an 710600, China"}]},{"given":"Wudian","family":"Kou","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"Key Laboratory of Precise Positioning and Timing Technology, Chinese Academy of Sciences, Xi\u2019an 710600, China"}]},{"given":"Shougang","family":"Zhang","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100039, China"},{"name":"Key Laboratory of Time and Frequency Standards, Chinese Academy of Sciences, Xi\u2019an 710600, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9852-9233","authenticated-orcid":false,"given":"Lu","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Software Engineering, Chengdu University of Information Technology, Chengdu 610225, China"}]},{"given":"Jun","family":"Lu","sequence":"additional","affiliation":[{"name":"School of Software Engineering, Chengdu University of Information Technology, Chengdu 610225, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Dardanelli, G., and Maltese, A. 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