{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T20:42:50Z","timestamp":1775076170022,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2019,6,12]],"date-time":"2019-06-12T00:00:00Z","timestamp":1560297600000},"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 paper reports on the research of factors that impact the accuracy and efficiency of an unmanned aerial vehicle (UAV) based radio frequency (RF) and microwave data collection system. The swarming UAVs (agents) can be utilized to create micro-UAV swarm-based (MUSB) aperiodic antenna arrays that reduce angle ambiguity and improve convergence in sub-space direction-of-arrival (DOA) techniques. A mathematical data model is addressed in this paper to demonstrate fundamental properties of MUSB antenna arrays and study the performance of the data collection system framework. The Cramer\u2013Rao bound (CRB) associated with two-dimensional (2D) DOAs of sources in the presence of sensor gain and phase coefficient is derived. The single-source case is studied in detail. The vector-space of emitters is exploited and the iterative-MUSIC (multiple signal classification) algorithm is created to estimate 2D DOAs of emitters. Numerical examples and practical measurements are provided to demonstrate the feasibility of the proposed MUSB data collection system framework using iterative-MUSIC algorithm and benchmark theoretical expectations.<\/jats:p>","DOI":"10.3390\/s19122659","type":"journal-article","created":{"date-parts":[[2019,6,12]],"date-time":"2019-06-12T10:55:19Z","timestamp":1560336919000},"page":"2659","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["A Sensor-Driven Analysis of Distributed Direction Finding Systems Based on UAV Swarms"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2635-1015","authenticated-orcid":false,"given":"Zhong","family":"Chen","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, Texas A&amp;M University, College Station, TX 77843-3128, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7734-4969","authenticated-orcid":false,"given":"Shihyuan","family":"Yeh","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Texas A&amp;M University, College Station, TX 77843-3128, USA"}]},{"given":"Jean-Francois","family":"Chamberland","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Texas A&amp;M University, College Station, TX 77843-3128, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7226-1723","authenticated-orcid":false,"given":"Gregory H.","family":"Huff","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science, Pennsylvania State University, University Park, PA 16802, USA"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"686","DOI":"10.1038\/161686a0","article-title":"Smoothing periodograms from time series with continuous spectra","volume":"161","author":"Bartlett","year":"1948","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1093\/biomet\/37.1-2.1","article-title":"Periodogram analysis and continuous spectra","volume":"37","author":"Bartlett","year":"1950","journal-title":"Biometrika"},{"key":"ref_3","unstructured":"Burg, J.P. 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