{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:06:47Z","timestamp":1760144807481,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,5,21]],"date-time":"2024-05-21T00:00:00Z","timestamp":1716249600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Network"],"abstract":"<jats:p>Indoor location services often use Bluetooth low energy (BLE) devices for their low energy consumption and easy implementation. Applications like device monitoring, ranging, and asset tracking utilize the received signal strength (RSS) of the BLE signal to estimate the proximity of a device from the receiver. However, in multipath environments, RSS-based solutions may not provide an accurate estimation. In such environments, receivers with antenna arrays are used to calculate the difference in time of flight (ToF) and therefore calculate the direction of arrival (DoA) of the Bluetooth signal. Other techniques like triangulation have also been used, such as having multiple transmitters or receivers as a network of sensors. To find a lost item, devices like Tile\u00a9 use an onboard beeper to notify users of their presence. In this paper, we present a system that uses a single-measurement device and describe the method of measurement to estimate the location of a BLE device using RSS. A BLE device is configured as an Eddystone beacon for periodic transmission of advertising packets with RSS information. We developed a smartphone application to read RSS information from the beacon, designed an algorithm to estimate the DoA, and used the phone\u2019s internal sensors to evaluate the DoA with respect to true north. The proposed measurement method allows for asset tracking by iterative measurements that provide the direction of the beacon and take the user closer at every step. The receiver application is easily deployable on a smartphone, and the algorithm provides direction of the beacon within a 30\u00b0 range, as suggested by the provided results.<\/jats:p>","DOI":"10.3390\/network4020010","type":"journal-article","created":{"date-parts":[[2024,5,21]],"date-time":"2024-05-21T06:50:52Z","timestamp":1716274252000},"page":"196-216","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Localization of a BLE Device Based on Single-Device RSSI and DOA Measurements"],"prefix":"10.3390","volume":"4","author":[{"given":"Harsha","family":"Kandula","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, University of North Texas, 1155 Union Circle #310470, Denton, TX 76203, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6153-110X","authenticated-orcid":false,"given":"Veena","family":"Chidurala","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Miami University, 501 E High St., Oxford, OH 45056, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuan","family":"Cao","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, University of North Texas, 1155 Union Circle #310470, Denton, TX 76203, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7954-243X","authenticated-orcid":false,"given":"Xinrong","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, University of North Texas, 1155 Union Circle #310470, Denton, TX 76203, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,21]]},"reference":[{"key":"ref_1","unstructured":"(2023, August 01). Bluetooth SIG, Inc., Market Update. Available online: https:\/\/www.bluetooth.com\/2023-market-update\/."},{"key":"ref_2","unstructured":"Townsend, K., Cuf\u00ed, C., and Robert, D. (2014). Getting Started with Bluetooth Low Energy, O\u2019Reilly Media, Inc.. [1st ed.]."},{"key":"ref_3","unstructured":"(2023, August 01). Beacon Market Size, Share & Industry Analysis, by Component (Hardware and Platform\/Software Development Kit (SDK)), by Connectivity Type (Bluetooth Low Energy (BLE), Wi-Fi, Hybrid and Others), by Deployment (Indoor and Outdoor), by End-Use (Residential and Commercial) and Regional Forecast, 2019\u20132026. Report ID: FBI100142. Available online: https:\/\/www.fortunebusinessinsights.com\/industry-reports\/toc\/beacon-market-100142."},{"key":"ref_4","unstructured":"(2023, August 01). The Tile App, Lost and Found Stories. Available online: https:\/\/www.thetileapp.com\/blog\/lost-and-found-facts."},{"key":"ref_5","unstructured":"Chipolo (2023, August 01). Find You Keys, Wallet or Anything You Don\u2019t Want to Lose. Available online: https:\/\/chipolo.net\/en-us\/."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"30728","DOI":"10.1109\/JSEN.2023.3328711","article-title":"Multichannel and Multi-RSS Based BLE Range Estimation for Indoor Tracking of Commercial Smartphones","volume":"23","author":"Guo","year":"2023","journal-title":"IEEE Sens. J."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Debnath, S., and O\u2019Keefe, K. (2023, January 25\u201328). Proximity Estimation with BLE RSSI and UWB Range Using Machine Learning Algorithm. Proceedings of the 13th IEEE International Conference on Indoor Positioning and Indoor Navigation (IPIN), Nuremberg, Germany.","DOI":"10.1109\/IPIN57070.2023.10332225"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Kalabakov, S., Svigelj, A., and Javornik, T. (2022, January 22\u201324). Smartphone Proximity Detection Using WiFi and BLE Fingerprinting. Proceedings of the IEEE International Balkan Conference on Communications and Networking (BalkanCom), Sarajevo, Bosnia and Herzegovina.","DOI":"10.1109\/BalkanCom55633.2022.9900709"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Park, Y.-B., and Lee, Y.H. (2021, January 20\u201322). A Novel Unified Trilateration Method for RSSI Based Indoor Localization. Proceedings of the International Conference on Information and Communication Technology Convergence (ICTC), Jeju Island, Republic of Korea.","DOI":"10.1109\/ICTC52510.2021.9621028"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Shu, W., Wang, S., and Zhai, B. (2023, January 10\u201312). Trilateration System Based on Bluetooth Distance Measurement Principle. Proceedings of the 9th International Conference on Mechatronics and Robotics Engineering (ICMRE), Shenzhen, China.","DOI":"10.1109\/ICMRE56789.2023.10106526"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Pakanon, N., Chamchoy, M., and Supanakoon, P. (2020, January 1\u20134). Study on Accuracy of Trilateration Method for Indoor Positioning with BLE Beacons. Proceedings of the 6th International Conference on Engineering, Applied Sciences and Technology (ICEAST), Chiang Mai, Thailand.","DOI":"10.1109\/ICEAST50382.2020.9165464"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Elhusseiny, A.H., Zamzam, M., and Zaghloul, Y. (2023, January 19\u201321). Precision Localization: An Experimental Study on BLE Fingerprinting and Trilateration with ESP32. Proceedings of the International Conference on Advances in Electronics, Communication, Computing and Intelligent Information Systems (ICAECIS), Bangalore, India.","DOI":"10.1109\/ICAECIS58353.2023.10170249"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"30176","DOI":"10.1109\/ACCESS.2024.3368449","article-title":"Augmentation of Fingerprints for Indoor BLE Localization Using Conditional GANs","volume":"12","author":"Junoh","year":"2024","journal-title":"IEEE Access"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"4388","DOI":"10.1109\/TMC.2022.3162612","article-title":"A Kernel Method to Nonlinear Location Estimation with RSS-Based Fingerprint","volume":"22","author":"Ng","year":"2023","journal-title":"IEEE Trans. Mob. Comput."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Jain, C., Sashank, G.V.S., and Markkandan, S. (2021, January 25\u201327). Low-Cost BLE Based Indoor Localization Using RSSI Fingerprinting and Machine Learning. Proceedings of the Sixth International Conference on Wireless Communications, Signal Processing and Networking (WiSPNET), Chennai, India.","DOI":"10.1109\/WiSPNET51692.2021.9419388"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Li, J., and Komuro, N. (2022, January 6\u20138). Fingerprint-Based BLE Indoor Position Methods to Improve Localization Accuracy by Particle Filters. Proceedings of the IEEE International Conference on Consumer Electronics, Taipei, Taiwan.","DOI":"10.1109\/ICCE-Taiwan55306.2022.9869173"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Faye, A., Sene, M., and Ndaw, J. (2021, January 23\u201324). RSS-Based Improved DOA Estimation Using SVM. Proceedings of the International Conference on Radar, Antenna, Microwave, Electronics, and Telecommunications (ICRAMET), Bandung, Indonesia.","DOI":"10.1109\/ICRAMET53537.2021.9650458"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Abu-Sardanah, S., Loher, J., Guarisma, Y., Dobre, D., Soni, K., Ramahi, O., and Shaker, G. (2023, January 7\u20139). Experimental Investigation on the Performance of Angle-of-Arrival-Based Asset Localization in a Warehouse. Proceedings of the International Microwave and Antenna Symposium (IMAS), Cairo, Egypt.","DOI":"10.1109\/IMAS55807.2023.10066896"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"153116","DOI":"10.1109\/ACCESS.2021.3127908","article-title":"Locating Objects in Warehouses Using BLE Beacons & Machine Learning","volume":"9","author":"Zadgaonkar","year":"2021","journal-title":"IEEE Access"},{"key":"ref_20","unstructured":"(2023, August 01). Air Tag. Available online: https:\/\/www.apple.com\/airtag\/."},{"key":"ref_21","unstructured":"(2023, August 01). Samsung Tag. Available online: https:\/\/www.samsung.com\/us\/mobile\/mobile-accessories\/phones\/galaxy-smarttag2-black-ei-t5600bbegus."},{"key":"ref_22","unstructured":"Torvmark, K. (2013). Texas Instruments White Paper, EDN Magazine."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Pramukantoro, E.S., and Gofuku, A. (2021, January 9\u201311). A Study of Bluetooth Low Energy (BLE) Frameworks on the IoT Based Heart Monitoring System. Proceedings of the IEEE 3rd Global Conference on Life Sciences and Technologies (LifeTech), Nara, Japan.","DOI":"10.1109\/LifeTech52111.2021.9391777"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Roy, P., Mondal, S., Biswas, A., and Banerjee, R. (2024, January 4\u20136). A Comprehensive Study on BLE Enabled IoT Based Tracking System (BITS) for Indoor Environment. Proceedings of the 2nd International Conference on Intelligent Data Communication Technologies and Internet of Things (IDCIoT), Bengaluru, India.","DOI":"10.1109\/IDCIoT59759.2024.10467984"},{"key":"ref_25","unstructured":"Bluetooth SIG (2021, June 01). Bluetooth Specifications: Specifications List. Available online: https:\/\/www.bluetooth.com\/specifications\/specs\/."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"315","DOI":"10.3390\/network1030018","article-title":"Measurement and analysis of RSS using Bluetooth mesh network for localization applications","volume":"1","author":"Cao","year":"2021","journal-title":"Network"},{"key":"ref_27","unstructured":"Apple (2021, December 01). Getting Heading and Course Information. Apple Developer Documentation. Available online: https:\/\/developer.apple.com\/documentation\/corelocation\/getting_heading_and_course_information."},{"key":"ref_28","unstructured":"Google (2021, December 01). Position Sensors. Android Developers Docs. Available online: https:\/\/developer.android.com\/guide\/topics\/sensors\/sensors_position."},{"key":"ref_29","unstructured":"Apple and Google (2021, December 01). Exposure Notification. Bluetooth Specification, April 2020. Available online: https:\/\/covid19.apple.com\/contacttracing."},{"key":"ref_30","unstructured":"NXP (2021, December 01). BLE Antenna Design Guide. Application Note, No. UM10992, Rev. 2.0, May 2018. Available online: https:\/\/www.nxp.com\/docs\/en\/user-guide\/UM10992.pdf."},{"key":"ref_31","unstructured":"Ellisys (2021, December 01). Understanidng Antenna Radiation Patterns. Ellisys Expert Note, No. EEN_BT05, Rev. B, September 2021. Available online: https:\/\/www.ellisys.com\/technology\/een_bt05.pdf."},{"key":"ref_32","unstructured":"Manolakis, D.G., Ingle, V.K., and Kogon, S.M. (2000). Statistical and Adaptive Signal Processing, McGraw-Hill."}],"container-title":["Network"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2673-8732\/4\/2\/10\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T14:45:42Z","timestamp":1760107542000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2673-8732\/4\/2\/10"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,5,21]]},"references-count":32,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2024,6]]}},"alternative-id":["network4020010"],"URL":"https:\/\/doi.org\/10.3390\/network4020010","relation":{},"ISSN":["2673-8732"],"issn-type":[{"type":"electronic","value":"2673-8732"}],"subject":[],"published":{"date-parts":[[2024,5,21]]}}}