{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:31:16Z","timestamp":1760236276962,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2021,11,6]],"date-time":"2021-11-06T00:00:00Z","timestamp":1636156800000},"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>Phased array technology features rapid and directional scanning and has become a promising approach for remote sensing and wireless communication. In addition, element-level digitization has increased the feasibility of complicated signal processing and simultaneous multi-beamforming processes. However, the high cost and bulky characteristics of beam-steering systems have prevented their extensive application. In this paper, an X-band element-level digital phased array radar utilizing fully integrated complementary metal-oxide-semiconductor (CMOS) transceivers is proposed for achieving a low-cost and compact-size digital beamforming system. An 8\u201310 GHz transceiver system-on-chip (SoC) fabricated in 65 nm CMOS technology offers baseband filtering, frequency translation, and global clock synchronization through the proposed periodic pulse injection technique. A 16-element subarray module with an SoC integration, antenna-in-package, and tile array configuration achieves digital beamforming, back-end computing, and dc\u2013dc conversion with a size of 317 \u00d7 149 \u00d7 74.6 mm3. A radar demonstrator with scalable subarray modules simultaneously realizes range sensing and azimuth recognition for pulsed radar configurations. Captured by the suggested software-defined pulsed radar, a complete range\u2013azimuth figure with a 1 km maximum observation range can be displayed within 150 ms under the current implementation.<\/jats:p>","DOI":"10.3390\/s21217382","type":"journal-article","created":{"date-parts":[[2021,11,7]],"date-time":"2021-11-07T20:42:54Z","timestamp":1636317774000},"page":"7382","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["An X-Band CMOS Digital Phased Array Radar from Hardware to Software"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2249-4294","authenticated-orcid":false,"given":"Yue-Ming","family":"Wu","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan"}]},{"given":"Hao-Chung","family":"Chou","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan"}]},{"given":"Cheng-Yung","family":"Ke","sequence":"additional","affiliation":[{"name":"Tron Future Tech Inc., Hsinchu 300042, Taiwan"}]},{"given":"Chien-Cheng","family":"Wang","sequence":"additional","affiliation":[{"name":"Tron Future Tech Inc., Hsinchu 300042, Taiwan"}]},{"given":"Chien-Te","family":"Li","sequence":"additional","affiliation":[{"name":"Tron Future Tech Inc., Hsinchu 300042, Taiwan"}]},{"given":"Li-Han","family":"Chang","sequence":"additional","affiliation":[{"name":"Tron Future Tech Inc., Hsinchu 300042, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8617-2601","authenticated-orcid":false,"given":"Borching","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0012-1745","authenticated-orcid":false,"given":"Ta-Shun","family":"Chu","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2534-1069","authenticated-orcid":false,"given":"Yu-Jiu","family":"Wang","sequence":"additional","affiliation":[{"name":"Tron Future Tech Inc., Hsinchu 300042, Taiwan"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"519","DOI":"10.1109\/JPROC.2015.2494879","article-title":"The Evolution to Modern Phased Array Architectures","volume":"104","author":"Herd","year":"2016","journal-title":"Proc. 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