{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T04:19:19Z","timestamp":1788409159329,"version":"build-2803163510"},"reference-count":40,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,11,29]],"date-time":"2020-11-29T00:00:00Z","timestamp":1606608000000},"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>This research proposes a through-wall S-band ultra-wideband (UWB) switched-antenna-array radar scheme for detection of stationary human subjects from respiration. The proposed antenna-array radar consists of one transmitting (Tx) and five receiving antennas (Rx). The Tx and Rx antennas are of Vivaldi type with high antenna gain (10 dBi) and narrow-angle directivity. The S-band frequency (2\u20134 GHz) is capable of penetrating non-metal solid objects and detecting human respiration behind a solid wall. Under the proposed radar scheme, the reflected signals are algorithmically preprocessed and filtered to remove unwanted signals, and 3D signal array is converted into 2D array using statistical variance. The images are reconstructed using back-projection algorithm prior to Sinc-filtered refinement. To validate the detection performance of the through-wall UWB radar scheme, simulations are carried out and experiments performed with single and multiple real stationary human subjects and a mannequin behind the concrete wall. Although the proposed method is an odd concept, the interest of this paper is applying the 1-Tx\/5-Rx UWB switched-antenna array radar with the proposed method that is capable of distinguishing between the human subjects and the mannequin behind the concrete wall.<\/jats:p>","DOI":"10.3390\/s20236828","type":"journal-article","created":{"date-parts":[[2020,11,29]],"date-time":"2020-11-29T21:00:57Z","timestamp":1606683657000},"page":"6828","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["1-Tx\/5-Rx Through-Wall UWB Switched-Antenna-Array Radar for Detecting Stationary Humans"],"prefix":"10.3390","volume":"20","author":[{"given":"Artit","family":"Rittiplang","sequence":"first","affiliation":[{"name":"School of Engineering, King Mongkut\u2019s Institute of Technology Ladkrabang, Bangkok 10520, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2387-6059","authenticated-orcid":false,"given":"Pattarapong","family":"Phasukkit","sequence":"additional","affiliation":[{"name":"School of Engineering, King Mongkut\u2019s Institute of Technology Ladkrabang, Bangkok 10520, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"620","DOI":"10.13164\/re.2018.0620","article-title":"Extended Noise Analysis Model of CW-type Radar Sensors with IQ Down-Conversion","volume":"27","author":"Jenik","year":"2018","journal-title":"Radioengineering"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Tantiparimongkol, L., and Phasukkit, P. (2019, January 10\u201313). Designing of UWB Pulse Generation in FPGA Based on Delay Line Method for Human Range Through the Wall Detecting Application. Proceedings of the 16th International Conference on Electrical Engineering\/Electronics, Computer, Telecommunications and Information Technology (ECTI-CON) 2019, Pattaya, Chonburi, Thailand.","DOI":"10.1109\/ECTI-CON47248.2019.8955368"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Rittiplang, A., Phasukkit, P., and Orankitanun, T. (2020). Optimal Central Frequency for Non-Contact Vital Sign Detection Using Monocycle UWB Radar. Sensors, 20.","DOI":"10.3390\/s20102916"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1199","DOI":"10.1109\/LGRS.2018.2834501","article-title":"Building Layout Reconstruction in Concealed Human Target Sensing via UWB MIMO Through-Wall Imaging Radar","volume":"15","author":"Song","year":"2018","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"730","DOI":"10.13164\/re.2016.0730","article-title":"Sidelobe Suppression Featuring the Phase Coherence Factor in 3-D Through-the-Wall Radar Imaging","volume":"25","author":"Anwar","year":"2016","journal-title":"Radioengineering"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Liang, F., Qi, F., An, Q., Lv, H., Chen, F., Li, Z., and Wang, J. (2016). Detection of Multiple Stationary Humans Using UWB MIMO Radar. Sensors, 16.","DOI":"10.3390\/s16111922"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"518","DOI":"10.13164\/re.2015.0518","article-title":"Design and Implementation of a FPGA and DSP Based MIMO Radar Imaging System","volume":"24","author":"Wang","year":"2015","journal-title":"Radioengineering"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Li, J., Liu, Y., Xu, H., Wang, B., Liu, L., and Chen, X. (2019). A High Signal\u2013Noise Ratio UWB Radar for Buried Pipe Location Using Golay Complementary Sequences. Appl. Sci., 9.","DOI":"10.3390\/app9235090"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"592","DOI":"10.13164\/re.2016.0592","article-title":"Beam Footprint Detection and Tracking for Non-Cooperative Bistatic SAR","volume":"25","author":"Yan","year":"2016","journal-title":"Radioengineering"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"581","DOI":"10.13164\/re.2016.0581","article-title":"Strong Spurious Noise Suppression for an FMCW SAR","volume":"25","author":"Tian","year":"2016","journal-title":"Radioengineering"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1986","DOI":"10.1109\/TGRS.2011.2170694","article-title":"Advanced System Level Simulation Platform for Three-Dimensional UWB Through-Wall Imaging SAR Using Time-Domain Approach","volume":"50","author":"Wang","year":"2012","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1109\/TGRS.2012.2199120","article-title":"MIMO Radar and Ground-Based SAR Imaging Systems: Equivalent Approaches for Remote Sensing","volume":"51","author":"Tarchi","year":"2013","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"442","DOI":"10.1109\/TAES.2017.2760758","article-title":"MIMO Radar Calibration and Imagery for Near-Field Scattering Diagnosis","volume":"54","author":"Liu","year":"2018","journal-title":"IEEE Trans. Aerospace Electr. Syst."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"298","DOI":"10.1109\/TGRS.2017.2746739","article-title":"A Portable 3-D Imaging FMCW MIMO Radar Demonstrator With a 24\u00d724 Antenna Array for Medium-Range Applications","volume":"56","author":"Ganis","year":"2018","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"3749","DOI":"10.1109\/TGRS.2014.2382672","article-title":"Ultrawideband Synthetic Aperture Radar for Respiratory Motion Detection","volume":"53","author":"Chen","year":"2015","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"776","DOI":"10.13164\/re.2019.0776","article-title":"3-D MIMO Radar Imaging of Ship Target with Rotational Motions","volume":"28","author":"Wang","year":"2019","journal-title":"Radioengineering"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"337","DOI":"10.13164\/re.2017.0337","article-title":"A Cascaded Reduced-Dimension STAP Method for Airborne MIMO Radar in the Presence of Jammers","volume":"26","author":"Wang","year":"2017","journal-title":"Radioengineering"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"194","DOI":"10.13164\/re.2016.0194","article-title":"A Novel Data Association Method for Frequency Based MIMO Systems","volume":"25","author":"Kalkan","year":"2016","journal-title":"Radioengineering"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Hu, Z., Zeng, Z., Wang, K., Feng, W., Zhang, J., Lu, Q., and Kang, X. (2019). Design and Analysis of a UWB MIMO Radar System with Miniaturized Vivaldi Antenna for Through-Wall Imaging. Remote Sens., 11.","DOI":"10.3390\/rs11161867"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"119","DOI":"10.2528\/PIERC18062004","article-title":"Through the Wall Imaging of Human Vital Signs Based on UWB MIMO Bioradar","volume":"87","author":"Liang","year":"2018","journal-title":"Progress Electromagn. Res. C"},{"key":"ref_21","unstructured":"Savelyev, T.G., Zhuge, X., Yarovoy, A.G., Ligthart, L.P., and Levitas, B. (October, January 30). Comparison of UWB SAR and MIMO-based short-range imaging radars. Proceedings of the 2009 European Radar Conference (EuRAD), Rome, Italy."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2594","DOI":"10.1109\/TAP.2010.2050424","article-title":"A Through-Dielectric Radar Imaging System","volume":"58","author":"Charvat","year":"2010","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"5495","DOI":"10.1109\/TAP.2012.2207663","article-title":"A Through-Dielectric Ultrawideband (UWB) Switched-Antenna-Array Radar Imaging System","volume":"60","author":"Charvat","year":"2012","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Charvat, G.L., Kempel, L.C., Rothwell, E.J., Coleman, C.M., and Mokole, E.L. (2010, January 12\u201315). An ultrawideband (UWB) switched-antenna-array radar imaging system. Proceedings of the 2010 IEEE International Symposium on Phased Array Systems and Technology, Waltham, MA, USA.","DOI":"10.1109\/ARRAY.2010.5613313"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Ralston, T.S., Charvat, G.L., and Peabody, J.E. (2010, January 12\u201315). Real-time through-wall imaging using an ultrawideband multiple-input multiple-output (MIMO) phased array radar system. Proceedings of the 2010 IEEE International Symposium on Phased Array Systems and Technology, Waltham, MA, USA.","DOI":"10.1109\/ARRAY.2010.5613314"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Sandora, J.S., and Charvat, G.L. (2013, January 15\u201318). An ultra-wideband Vivaldi and linear hybrid taper antenna for use in a near-field real-time phased array radar system. Proceedings of the 2013 IEEE International Symposium on Phased Array Systems and Technology, Waltham, MA, USA.","DOI":"10.1109\/ARRAY.2013.6731846"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2252","DOI":"10.1109\/TAP.2012.2189697","article-title":"Taper Design of Vivaldi and Co-Planar Tapered Slot Antenna (TSA) by Chebyshev Transformer","volume":"60","author":"Ebnabbasi","year":"2012","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_28","first-page":"92","article-title":"UWB Vivaldi Antenna Array Lower Band Improvement for Ground Penetrating Radar Applications","volume":"28","author":"Diet","year":"2019","journal-title":"Radioengineering"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"111","DOI":"10.2528\/PIERC18051502","article-title":"An Ultra-Wideband Modified Vivaldi Antenna Applied to Ground and Through the Wall Imaging","volume":"86","author":"Tahar","year":"2018","journal-title":"Progress Electromagn. Res. C"},{"key":"ref_30","unstructured":"Eko Setijadi, N., and Hendrantoro, G. (2016, January 9\u201311). Comparison study of S-Band Vivaldi-based antennas. Proceedings of the 2016 IEEE Region 10 Symposium (TENSYMP), Bali, Indonesia."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"651","DOI":"10.1049\/iet-map.2015.0585","article-title":"Design of an X-band Vivaldi antenna with low radar cross section","volume":"10","author":"Natarajan","year":"2016","journal-title":"IET Microw. Antennas Propag."},{"key":"ref_32","first-page":"35","article-title":"High Gain Vivaldi Antenna for Radar and Microwave Imaging Applications","volume":"3","author":"Pandey","year":"2015","journal-title":"Int. J. Signal Process. Syst."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Kaemarungsi, K., Athikulwongse, K., Rungprateepthaworn, K., Duangtanoo, T., and Dangsakul, P. (2015, January 24\u201327). On study of an impulse RADAR sensor for subsurface object detection. Proceedings of the 12th International Conference on Electrical Engineering\/Electronics, Computer, Telecommunications and Information Technology, ECTI-CON 2015, Hua Hin, Thailand.","DOI":"10.1109\/ECTICon.2015.7207083"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Liang, X., Wang, Y., Wu, S., and Gulliver, T.A. (2018). Experimental Study of Wireless Monitoring of Human Respiratory Movements Using UWB Impulse Radar Systems. Sensors, 18.","DOI":"10.3390\/s18093065"},{"key":"ref_35","unstructured":"Rittiplang, A., and Phasukkit, P. (2018, January 29\u201331). Human Movement Detection behind the Wall based on Doppler Frequency and Standard Deviation. Proceedings of the 2018 International Symposium on Multimedia and Communication Technology (ISMAC), Tottori, Japan."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Rittiplang, A., and Phasukkit, P. (2019, January 19\u201322). UWB Radar for Multiple Human Detection Through the Wall Based on Doppler Frequency and Variance Statistic. Proceedings of the 2019 12th Biomedical Engineering International Conference (BMEiCON), Ubon Ratchathani, Thailand.","DOI":"10.1109\/BMEiCON47515.2019.8990358"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Tantiparimongkol, L., and Phasukkit, P. (2020). IR-UWB Pulse Generation Using FPGA Scheme for through Obstacle Human Detection. Sensors, 20.","DOI":"10.3390\/s20133750"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"22101","DOI":"10.1109\/ACCESS.2017.2761771","article-title":"An Improved Algorithm for Through-Wall Target Detection Using Ultra-Wideband Impulse Radar","volume":"5","author":"Liang","year":"2017","journal-title":"IEEE Access"},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Yang, S., Qin, H., Liang, X., and Gulliver, T.A. (2019). Clutter Elimination and Harmonic Suppression of Non-Stationary Life Signs for Long-Range and Through-Wall Human Subject Detection Using Spectral Kurtosis Analysis (SKA)-Based Windowed Fourier Transform (WFT) Method. Appl. Sci., 9.","DOI":"10.3390\/app9020355"},{"key":"ref_40","unstructured":"Barrie, G. (2003). Ultra-Wideband Synthetic Aperture Imaging, Data and Image Processing, (DRDC Ottawa TM 2003-015), Defence R&D Canada."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/23\/6828\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:39:16Z","timestamp":1760179156000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/23\/6828"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,11,29]]},"references-count":40,"journal-issue":{"issue":"23","published-online":{"date-parts":[[2020,12]]}},"alternative-id":["s20236828"],"URL":"https:\/\/doi.org\/10.3390\/s20236828","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,11,29]]}}}