{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T08:10:49Z","timestamp":1778746249721,"version":"3.51.4"},"reference-count":33,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,4,2]],"date-time":"2021-04-02T00:00:00Z","timestamp":1617321600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2021R1G1A1007836"],"award-info":[{"award-number":["2021R1G1A1007836"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we introduce mapping results in an indoor environment based on our own developed dual-mode radar sensor. Our radar system uses a frequency-modulated continuous wave (FMCW) with a center frequency of 62 GHz and a multiple-input multiple-output antenna system. In addition, the FMCW radar sensor we designed is capable of dual-mode detection, which alternately transmits two waveforms using different bandwidths within one frame. The first waveform is for long-range detection, and the second waveform is for short-range detection. This radar system is mounted on a small robot that moves in indoor environments such as rooms or hallways, and the radar and the robot send and receive necessary information to each other. The radar estimates the distance, velocity, and angle information of targets around the radar-equipped robot. Then, the radar receives information about the robot\u2019s motion from the robot, such as its speed and rotation angle. Finally, by combining the motion information and the detection results, the radar-equipped robot maps the indoor environment while finding its own position. Compared to the actual map data, the radar-based mapping is effectively achieved through the radar system we developed.<\/jats:p>","DOI":"10.3390\/s21072469","type":"journal-article","created":{"date-parts":[[2021,4,2]],"date-time":"2021-04-02T10:34:09Z","timestamp":1617359649000},"page":"2469","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Dual-Mode Radar Sensor for Indoor Environment Mapping"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9115-4897","authenticated-orcid":false,"given":"Seongwook","family":"Lee","sequence":"first","affiliation":[{"name":"School of Electronics and Information Engineering, College of Engineering, Korea Aerospace University, Gyeonggi-do 10540, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Song-Yi","family":"Kwon","sequence":"additional","affiliation":[{"name":"School of Electronics and Information Engineering, College of Engineering, Korea Aerospace University, Gyeonggi-do 10540, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bong-Jun","family":"Kim","sequence":"additional","affiliation":[{"name":"Bitsensing Inc., Seoul 06247, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hae-Seung","family":"Lim","sequence":"additional","affiliation":[{"name":"Bitsensing Inc., Seoul 06247, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3326-3467","authenticated-orcid":false,"given":"Jae-Eun","family":"Lee","sequence":"additional","affiliation":[{"name":"Bitsensing Inc., Seoul 06247, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Dei\u00dfler, T., and Thielecke, J. 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