{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T16:10:55Z","timestamp":1781885455537,"version":"3.54.5"},"reference-count":50,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2022,6,10]],"date-time":"2022-06-10T00:00:00Z","timestamp":1654819200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"International Funding","award":["IF071-2020"],"award-info":[{"award-number":["IF071-2020"]}]},{"name":"International Funding","award":["RK002-2021"],"award-info":[{"award-number":["RK002-2021"]}]},{"name":"International Funding","award":["SKL-AMSV(UM)-2020-2022"],"award-info":[{"award-number":["SKL-AMSV(UM)-2020-2022"]}]},{"name":"Partnership Grant","award":["IF071-2020"],"award-info":[{"award-number":["IF071-2020"]}]},{"name":"Partnership Grant","award":["RK002-2021"],"award-info":[{"award-number":["RK002-2021"]}]},{"name":"Partnership Grant","award":["SKL-AMSV(UM)-2020-2022"],"award-info":[{"award-number":["SKL-AMSV(UM)-2020-2022"]}]},{"name":"Macau Science and Technology Development Fund (FDCT)","award":["IF071-2020"],"award-info":[{"award-number":["IF071-2020"]}]},{"name":"Macau Science and Technology Development Fund (FDCT)","award":["RK002-2021"],"award-info":[{"award-number":["RK002-2021"]}]},{"name":"Macau Science and Technology Development Fund (FDCT)","award":["SKL-AMSV(UM)-2020-2022"],"award-info":[{"award-number":["SKL-AMSV(UM)-2020-2022"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper proposes a 2.4-GHz fully-integrated single-frequency multi-channel RF energy harvesting (RFEH) system with increased harvested power density. The RFEH can produce an output power of ~423-\u03bcW in harvesting ambient RF energy. The front-end consists of an on-chip impedance matching network with a stacked rectifier concurrently matched to a 50 \u03a9 input source. The circuit mitigates the \u201cdead-zone\u201d by enhancing the pumping efficiency, achieved through the increase of Vgs drivability of the proposed internal gate boosting 6-stage low-input voltage charge pump and the 5-stage shared-auxiliary-biasing ring-voltage-controlled-oscillator (VCO) integrated to improve the start-up. The RFEH system, simulated in 180-nm complementary metal\u2013oxide\u2013semiconductor (CMOS), occupies an active area of 1.02 mm2. Post-layout simulations show a peak power conversion efficiency(PCE) of 21.15%, driving a 3.3-k\u03a9 load at an input power of 0 dBm and sensitivity of \u221214.1 dBm corresponding to an output voltage, Vout,RFEH of 1.25 V.<\/jats:p>","DOI":"10.3390\/s22124415","type":"journal-article","created":{"date-parts":[[2022,6,13]],"date-time":"2022-06-13T02:01:44Z","timestamp":1655085704000},"page":"4415","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["A Fully-Integrated Ambient RF Energy Harvesting System with 423-\u03bcW Output Power"],"prefix":"10.3390","volume":"22","author":[{"given":"Kishore Kumar","family":"Pakkirisami Churchill","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harikrishnan","family":"Ramiah","sequence":"additional","affiliation":[{"name":"Centre of Research Industry 4.0 (CRI 4.0), Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriel","family":"Chong","sequence":"additional","affiliation":[{"name":"Nexperia R&D Penang, Bayan Lepas 11900, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2794-1324","authenticated-orcid":false,"given":"Yong","family":"Chen","sequence":"additional","affiliation":[{"name":"State-Key Laboratory of Analog and Mixed-Signal VLSI\/IME, Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Macau 999078, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pui-In","family":"Mak","sequence":"additional","affiliation":[{"name":"State-Key Laboratory of Analog and Mixed-Signal VLSI\/IME, Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Macau 999078, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rui P.","family":"Martins","sequence":"additional","affiliation":[{"name":"State-Key Laboratory of Analog and Mixed-Signal VLSI\/IME, Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Macau 999078, China"},{"name":"Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1099-085 Lisboa, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Basim, M., Khan, D., Ain, Q.U., Shehzad, K., Shah, S.A.A., Jang, B.-G., Pu, Y.-G., Yoo, J.-M., Kim, J.-T., and Lee, K.-Y. 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