eprintid: 1534616 rev_number: 43 eprint_status: archive userid: 608 dir: disk0/01/53/46/16 datestamp: 2017-03-08 14:23:35 lastmod: 2021-09-30 22:34:24 status_changed: 2017-06-27 14:05:26 type: proceedings_section metadata_visibility: show creators_name: Chen, Q creators_name: Chetty, K creators_name: Brennan, P creators_name: Lok, L title: A Coherent Through-Wall MIMO Phased Array Imaging Radar based on Time-Duplexed Switching ispublished: pub divisions: UCL divisions: B04 divisions: C05 divisions: F46 divisions: F52 keywords: Multiple Input Multiple Output Radar, Phase Array, Radar Imaging, Through Wall, Time-Duplexed radar note: This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions. abstract: Through-the-Wall (TW) radar sensors are gaining increasing interest for security, surveillance and search and rescue applications. Additionally, the integration of Multiple-Input, Multiple-Output (MIMO) techniques with phased array radar is allowing higher performance at lower cost. In this paper we present a 4-by-4 TW MIMO phased array imaging radar operating at 2.4 GHz with 200 MHz bandwidth. To achieve high imaging resolution in a cost-effective manner, the 4 Tx and 4 Rx elements are used to synthesize a uniform linear array (ULA) of 16 virtual elements. Furthermore, the transmitter is based on a single-channel 4-element time-multiplexed switched array. In transmission, the radar utilizes frequency modulated continuous wave (FMCW) waveforms that undergo de-ramping on receive to allow digitization at relatively low sampling rates, which then simplifies the imaging process. This architecture has been designed for the short-range TW scenarios envisaged, and permits sufficient time to switch between antenna elements. The paper first outlines the system characteristics before describing the key signal processing and imaging algorithms which are based on traditional Fast Fourier Transform (FFT) processing. These techniques are implemented in LabVIEW software. Finally, we report results from an experimental campaign that investigated the imaging capabilities of the system and demonstrated the detection of personnel targets. Moreover, we show that multiple targets within a room with greater than approximately 1 meter separation can be distinguished from one another. date: 2017-05-01 date_type: published publisher: Society of Photo-Optical Instrumentation Engineers (SPIE) official_url: http://dx.doi.org/10.1117/12.2262462 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 1200136 doi: 10.1117/12.2262462 lyricists_name: Brennan, Paul lyricists_name: Chen, Qingchao lyricists_name: Chetty, Kevin lyricists_name: Lok, Lai Bun lyricists_name: Ritchie, Matthew lyricists_name: Woodbridge, Karl lyricists_id: PVBRE73 lyricists_id: CHENK14 lyricists_id: KCHET45 lyricists_id: LBLOK59 lyricists_id: MARIT18 lyricists_id: KWOOD71 actors_name: Allington-Smith, Dominic actors_id: DAALL44 actors_role: owner full_text_status: public series: Proceedings of SPIE publication: Proceedings of SPIE - The International Society for Optical Engineering volume: 10188 place_of_pub: Anaheim, CA, USA event_title: Defense + Security 2017 Conference event_location: Anaheim, US event_dates: 09 April 2017 - 13 April 2017 institution: Defense + Security issn: 0277-786X book_title: Radar Sensor Technology XXI editors_name: Ranney, KI editors_name: Doerry, A citation: Chen, Q; Chetty, K; Brennan, P; Lok, L; (2017) A Coherent Through-Wall MIMO Phased Array Imaging Radar based on Time-Duplexed Switching. In: Ranney, KI and Doerry, A, (eds.) Radar Sensor Technology XXI. Society of Photo-Optical Instrumentation Engineers (SPIE): Anaheim, CA, USA. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/1534616/1/Chen_1018809.pdf