{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,29]],"date-time":"2025-10-29T03:41:19Z","timestamp":1761709279438,"version":"build-2065373602"},"reference-count":19,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2016,12,11]],"date-time":"2016-12-11T00:00:00Z","timestamp":1481414400000},"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>Time-Modulated Linear Arrays (TMLAs) offer useful efficiency savings over conventional phased arrays when applied in parameter estimation applications. The present paper considers the application of TMLAs to acoustic systems and proposes an algorithm for efficiently deriving the arrival angle of a signal. The proposed technique is applied in the frequency domain, where the signal and harmonic content is captured. Using a weighted average method on harmonic amplitudes and their respective main beam angles, it is possible to determine an estimate for the signal\u2019s direction of arrival. The method is demonstrated and evaluated using results from both numerical and practical implementations and performance data is provided. The use of Micro-Electromechanical Systems (MEMS) sensors allows time-modulation techniques to be applied at ultrasonic frequencies. Theoretical predictions for an array of five isotropic elements with half-wavelength spacing and 1000 data samples suggest an accuracy of     \u00b1  1 \u2218      within an angular range of approximately     \u00b1  50 \u2218     . In experiments of a 40 kHz five-element microphone array, a Direction of Arrival (DoA) estimation within     \u00b1 2 .  5 \u2218      of the target signal is readily achieved inside a     \u00b1  45 \u2218      range using a single switched input stage and a simple hardware setup.<\/jats:p>","DOI":"10.3390\/s16122107","type":"journal-article","created":{"date-parts":[[2016,12,12]],"date-time":"2016-12-12T14:43:57Z","timestamp":1481553837000},"page":"2107","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Acoustical Direction Finding with Time-Modulated Arrays"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6292-1708","authenticated-orcid":false,"given":"Ben","family":"Clark","sequence":"first","affiliation":[{"name":"Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Leicestershire LE11 3TU, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1508-1854","authenticated-orcid":false,"given":"James","family":"Flint","sequence":"additional","affiliation":[{"name":"Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Leicestershire LE11 3TU, UK"}]}],"member":"1968","published-online":{"date-parts":[[2016,12,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2098","DOI":"10.1121\/1.3089221","article-title":"Beamforming with Microphone Arrays for Directional Sources","volume":"125","author":"Bouchard","year":"2009","journal-title":"J. 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