{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:25:32Z","timestamp":1760239532120,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,12,3]],"date-time":"2020-12-03T00:00:00Z","timestamp":1606953600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002850","name":"Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["1151476","1151125","1161356"],"award-info":[{"award-number":["1151476","1151125","1161356"]}],"id":[{"id":"10.13039\/501100002850","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000181","name":"Air Force Office of Scientific Research","doi-asserted-by":"publisher","award":["FA9550-18-1-0249"],"award-info":[{"award-number":["FA9550-18-1-0249"]}],"id":[{"id":"10.13039\/100000181","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Radars are used to retrieve physical parameters related to clouds and fog. With these measurements, models can be developed for several application fields such as climate, agriculture, aviation, energy, and astronomy. In Chile, coastal fog and low marine stratus intersect the coastal topography, forming a thick fog essential to sustain coastal ecosystems. This phenomenon motivates the development of cloud radars to boost scientific research. In this article, we present the design of a Ka-band cloud radar and the experiments that prove its operation. The radar uses a frequency-modulated continuous-wave with a carrier frequency of 38 GHz. By using a drone and a commercial Lidar, we were able to verify that the radar can measure reflectivities in the order of \u221260 dBZ at 500 m of distance, with a range resolution of 20 m. The lower needed range coverage imposed by our case of study enabled a significant reduction of the instrument cost compared to existent alternatives. The portability and low-cost of the designed instrument enable its implementation in a distributed manner along the coastal mountain range, as well as its use in medium-size aerial vehicles or balloons to study higher layers. The main features, limitations, and possible improvements to the current instrument are discussed.<\/jats:p>","DOI":"10.3390\/rs12233965","type":"journal-article","created":{"date-parts":[[2020,12,3]],"date-time":"2020-12-03T11:15:43Z","timestamp":1606994143000},"page":"3965","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Low-Cost Ka-Band Cloud Radar System for Distributed Measurements within the Atmospheric Boundary Layer"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5574-8724","authenticated-orcid":false,"given":"Roberto","family":"Aguirre","sequence":"first","affiliation":[{"name":"Electrical Engineering Department, Faculty of Physical and Mathematical Sciences, University of Chile, Santiago 8370451, Chile"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6504-6657","authenticated-orcid":false,"given":"Felipe","family":"Toledo","sequence":"additional","affiliation":[{"name":"Laboratoire de M\u00e9t\u00e9orologie Dynamique, \u00c9cole Polytechnique, Institut Polytechnique de Paris, 91128 Palaiseau, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0874-4410","authenticated-orcid":false,"given":"Rafael","family":"Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Institute of Electricity and Electronics, Facultad de Ciencias de la Ingenier\u00eda, Universidad Austral, General Lagos 2086, Valdivia 5110701, Chile"},{"name":"CePIA, Astronomy Department, Universidad de Concepci\u00f3n, Casilla 160-C, Concepci\u00f3n 4030000, Chile"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7440-7810","authenticated-orcid":false,"given":"Roberto","family":"Rondanelli","sequence":"additional","affiliation":[{"name":"Department of Geophysics, Faculty of Physical and Mathematical Sciences, University of Chile, Santiago 8370449, Chile"},{"name":"Space and Planetary Exploration Laboratory, Faculty of Physical and Mathematical Sciences, University of Chile, Santiago 8370451, Chile"},{"name":"Center for Climate and Resilience Research, Faculty of Physical and Mathematical Sciences, University of Chile, Santiago 8370449, Chile"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8522-4315","authenticated-orcid":false,"given":"Nicolas","family":"Reyes","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, Faculty of Physical and Mathematical Sciences, University of Chile, Santiago 8370451, Chile"},{"name":"Max Planck Institute for Radioastronomy, Auf dem Hugel 69, 53121 Bonn, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7701-5839","authenticated-orcid":false,"given":"Marcos","family":"D\u00edaz","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, Faculty of Physical and Mathematical Sciences, University of Chile, Santiago 8370451, Chile"},{"name":"Space and Planetary Exploration Laboratory, Faculty of Physical and Mathematical Sciences, University of Chile, Santiago 8370451, Chile"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10811","DOI":"10.5194\/acp-17-10811-2017","article-title":"Radiation in fog: Quantification of the impact on fog liquid water based on ground-based remote sensing","volume":"17","author":"Haeffelin","year":"2017","journal-title":"Atmos. 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