{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,16]],"date-time":"2026-05-16T13:33:05Z","timestamp":1778938385857,"version":"3.51.4"},"reference-count":36,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,16]],"date-time":"2018-10-16T00:00:00Z","timestamp":1539648000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006041","name":"Innovate UK","doi-asserted-by":"publisher","award":["103920"],"award-info":[{"award-number":["103920"]}],"id":[{"id":"10.13039\/501100006041","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present a first prototype of a wideband microwave tomography system with potential application to medical imaging. The system relies on a compact and robust printed monopole antenna which can operate in the 1.0\u20133.0 GHz range when fully immersed in commonly used coupling liquids, such as glycerine\u2013water solutions. By simulating the proposed imaging setup in CST Microwave Studio, we study the signal transmission levels and array sensitivity for different target and coupling liquid media. We then present the experimental prototype design and data acquisition process, and show good agreement between experimentally measured data and results from the CST simulations. We assess imaging performance by applying our previously proposed two-dimensional (2-D) DBIM TwIST-algorithm to both simulated and experimental datasets, and demonstrate that the system can reconstruct simple cylindrical targets at multiple frequencies.<\/jats:p>","DOI":"10.3390\/s18103491","type":"journal-article","created":{"date-parts":[[2018,10,16]],"date-time":"2018-10-16T11:07:51Z","timestamp":1539688071000},"page":"3491","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Design and Experimental Validation of a Multiple-Frequency Microwave Tomography System Employing the DBIM-TwIST Algorithm"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7120-1051","authenticated-orcid":false,"given":"Syed","family":"Ahsan","sequence":"first","affiliation":[{"name":"Faculty of Natural and Mathematical Sciences, King\u2019s College London, Strand, London WC2B 4PH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ziwen","family":"Guo","sequence":"additional","affiliation":[{"name":"Faculty of Natural and Mathematical Sciences, King\u2019s College London, Strand, London WC2B 4PH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4009-1528","authenticated-orcid":false,"given":"Zhenzhuang","family":"Miao","sequence":"additional","affiliation":[{"name":"Faculty of Natural and Mathematical Sciences, King\u2019s College London, Strand, London WC2B 4PH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ioannis","family":"Sotiriou","sequence":"additional","affiliation":[{"name":"Faculty of Natural and Mathematical Sciences, King\u2019s College London, Strand, London WC2B 4PH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8084-5016","authenticated-orcid":false,"given":"Maria","family":"Koutsoupidou","sequence":"additional","affiliation":[{"name":"Faculty of Natural and Mathematical Sciences, King\u2019s College London, Strand, London WC2B 4PH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Efthymios","family":"Kallos","sequence":"additional","affiliation":[{"name":"MediWise Ltd., London E1 2AX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"George","family":"Palikaras","sequence":"additional","affiliation":[{"name":"MediWise Ltd., London E1 2AX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9759-2820","authenticated-orcid":false,"given":"Panagiotis","family":"Kosmas","sequence":"additional","affiliation":[{"name":"Faculty of Natural and Mathematical Sciences, King\u2019s College London, Strand, London WC2B 4PH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,16]]},"reference":[{"key":"ref_1","first-page":"3021","article-title":"Microwave tomography: Review of the progress towards clinical applications","volume":"367","author":"Semenov","year":"2009","journal-title":"Philos. 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