{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T02:48:09Z","timestamp":1777344489531,"version":"3.51.4"},"reference-count":28,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,12]],"date-time":"2023-06-12T00:00:00Z","timestamp":1686528000000},"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>A radar altimeter (RA) is useful to improve autonomous functions such as landing guidance or navigation control of an aircraft. To ensure more precise and safer flights by aircraft, an interferometric RA (IRA) capable of measuring the angle of a target is required. However, the phase-comparison monopulse (PCM) technique used in IRAs has a problem in that an angular ambiguity arises with respect to a target with multiple reflection points, such as terrain. In this paper, we propose an altimetry method for IRAs that reduces the angular ambiguity by evaluating the quality of the phase. The altimetry method as introduced here is sequentially described based on synthetic aperture radar, a delay\/Doppler radar altimeter, and PCM techniques. Finally, a phase quality evaluation method is proposed for use in the azimuth estimation process. Aircraft captive flight test results are presented and analyzed, and the validity of the proposed method is examined.<\/jats:p>","DOI":"10.3390\/s23125508","type":"journal-article","created":{"date-parts":[[2023,6,13]],"date-time":"2023-06-13T02:00:45Z","timestamp":1686621645000},"page":"5508","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Altimetry Method for an Interferometric Radar Altimeter Based on a Phase Quality Evaluation"],"prefix":"10.3390","volume":"23","author":[{"given":"Jong-Soo","family":"Ha","sequence":"first","affiliation":[{"name":"Agency for Defense Development, Yuseong P.O. Box 35, Daejeon 34186, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung-Yong","family":"Hong","sequence":"additional","affiliation":[{"name":"Department of Radio and Information Communication Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Carre\u00f1o, S., Wilson, P., Ridao, P., and Petillot, Y. (2010, January 20\u201323). A survey on terrain based navigation for AUVs. 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