{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T14:59:59Z","timestamp":1776783599864,"version":"3.51.2"},"reference-count":48,"publisher":"Association for Computing Machinery (ACM)","issue":"1","license":[{"start":{"date-parts":[[2017,8,21]],"date-time":"2017-08-21T00:00:00Z","timestamp":1503273600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.acm.org\/publications\/policies\/copyright_policy#Background"}],"funder":[{"name":"University Grants Committee of the Hong Kong Special Administrative Region, China","award":["AoE\/E-02\/08"],"award-info":[{"award-number":["AoE\/E-02\/08"]}]},{"name":"General Research","award":["411010 and 411011"],"award-info":[{"award-number":["411010 and 411011"]}]},{"DOI":"10.13039\/501100012166","name":"National Basic Research Program of China","doi-asserted-by":"crossref","award":["2012CB315904 and 2013CB336700"],"award-info":[{"award-number":["2012CB315904 and 2013CB336700"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["dl.acm.org"],"crossmark-restriction":true},"short-container-title":["ACM Trans. Intell. Syst. Technol."],"published-print":{"date-parts":[[2018,1,31]]},"abstract":"<jats:p>\n            It is a promising vision to exploit\n            <jats:italic>white spaces<\/jats:italic>\n            , that is, vacant VHF and UHF TV channels, to meet the rapidly growing demand for wireless data services in both outdoor and indoor scenarios. While most prior works have focused on outdoor white space, the indoor story is largely open for investigation. Motivated by this observation and discovering that 70% of the spectrum demand comes from indoor environment, we carry out a comprehensive study to explore\n            <jats:italic>indoor<\/jats:italic>\n            white spaces. We first conduct a large-scale measurement study and compare outdoor and indoor TV spectrum occupancy at 30+ diverse locations in a typical metropolis\u2014Hong Kong. Our results show that abundant white spaces are available in different areas in Hong Kong, which account for more than 50% and 70% of the entire TV spectrum in outdoor and indoor scenarios, respectively. Although there are substantially more white spaces indoors than outdoors, there have been very few solutions for identifying indoor white space. To fill in this gap, we develop the first data-driven, low-cost indoor white space identification system for White-space Indoor Spectrum EnhanceR (WISER), to allow secondary users to identify white spaces for communication without sensing the spectrum themselves. We design the architecture and algorithms to address the inherent challenges. We build a WISER prototype and carry out real-world experiments to evaluate its performance. Our results show that WISER can identify 30%--40% more indoor white spaces with negligible false alarms, as compared to alternative baseline approaches.\n          <\/jats:p>","DOI":"10.1145\/3059149","type":"journal-article","created":{"date-parts":[[2017,8,24]],"date-time":"2017-08-24T11:49:04Z","timestamp":1503575344000},"page":"1-25","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":11,"title":["Exploring Indoor White Spaces in Metropolises"],"prefix":"10.1145","volume":"9","author":[{"given":"Xuhang","family":"Ying","sequence":"first","affiliation":[{"name":"University of Washington"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jincheng","family":"Zhang","sequence":"additional","affiliation":[{"name":"The Chinese University of Hong Kong"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lichao","family":"Yan","sequence":"additional","affiliation":[{"name":"The Chinese University of Hong Kong"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6953-2115","authenticated-orcid":false,"given":"Yu","family":"Chen","sequence":"additional","affiliation":[{"name":"University of California, San Diego"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guanglin","family":"Zhang","sequence":"additional","affiliation":[{"name":"Donghua University"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Minghua","family":"Chen","sequence":"additional","affiliation":[{"name":"The Chinese University of Hong Kong"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ranveer","family":"Chandra","sequence":"additional","affiliation":[{"name":"Microsoft Research, Redmond"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"320","published-online":{"date-parts":[[2017,8,21]]},"reference":[{"key":"e_1_2_1_1_1","volume-title":"Proceedings of the 9th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON\u201912)","author":"Andreas","unstructured":"Andreas Achtzehn et al. 2012. Improving coverage prediction for primary multi-transmitter networks operating in the TV whitespaces . In Proceedings of the 9th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON\u201912) . IEEE. Andreas Achtzehn et al. 2012. Improving coverage prediction for primary multi-transmitter networks operating in the TV whitespaces. In Proceedings of the 9th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON\u201912). IEEE."},{"key":"e_1_2_1_2_1","volume-title":"Proceedings of the IEEE International Symposium on Dynamic Spectrum Access Networks (DYSPAN\u201914)","author":"Andreas","unstructured":"Andreas Achtzehn et al. 2014. Improving accuracy for TVWS geolocation databases: Results from measurement-driven estimation approaches . In Proceedings of the IEEE International Symposium on Dynamic Spectrum Access Networks (DYSPAN\u201914) . IEEE, 392--403. 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Retrieved from http:\/\/www.digitaltv.gov.hk\/general\/pdf\/coverage.pdf (2016)."},{"key":"e_1_2_1_7_1","doi-asserted-by":"publisher","DOI":"10.1109\/MCOM.2008.4623708"},{"key":"e_1_2_1_8_1","doi-asserted-by":"publisher","DOI":"10.1109\/JSAC.2013.131110"},{"key":"e_1_2_1_9_1","volume-title":"GNU Radio.","author":"Radio Community GNU","year":"2016","unstructured":"GNU Radio Community . 2016. GNU Radio. Retrieved from http:\/\/gnuradio.org\/redmine\/projects\/gnuradio\/wiki ( 2016 ). GNU Radio Community. 2016. GNU Radio. Retrieved from http:\/\/gnuradio.org\/redmine\/projects\/gnuradio\/wiki (2016)."},{"key":"e_1_2_1_10_1","volume-title":"Universal Software Radio Peripheral.","author":"ETTUS.","year":"2016","unstructured":"ETTUS. 2016. Universal Software Radio Peripheral. Retrieved from http:\/\/www.ettus.com ( 2016 ). ETTUS. 2016. Universal Software Radio Peripheral. 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In Proceedings of the IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN\u201912) . IEEE, 422--433. Caleb Phillips et al. 2012. Practical radio environment mapping with geostatistics. In Proceedings of the IEEE International Symposium on Dynamic Spectrum Access Networks (DySPAN\u201912). IEEE, 422--433."},{"key":"e_1_2_1_37_1","doi-asserted-by":"crossref","unstructured":"David Plets et al. 2009. Extensive penetration loss measurements and models for different building types for DVB-H in the UHF band. In IEEE Trans. Broadcast. Vol. 55. 213--222.  David Plets et al. 2009. Extensive penetration loss measurements and models for different building types for DVB-H in the UHF band. In IEEE Trans. Broadcast. 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Retrieved from http:\/\/www.ie.cuhk.edu.hk\/&sim;mhchen\/papers\/HK.measurement.2011.pdf. L. Yan and M. Chen. 2011. Exploring White Spaces in Metropolises: A Measurement Study in Hong Kong. Technical Report. The Chinese University of Hong Kong. Retrieved from http:\/\/www.ie.cuhk.edu.hk\/&sim;mhchen\/papers\/HK.measurement.2011.pdf."},{"key":"e_1_2_1_43_1","doi-asserted-by":"publisher","DOI":"10.1109\/TMC.2011.128"},{"key":"e_1_2_1_44_1","volume-title":"Proceedings of the 7th International Conference on Communication Systems and Networks (COMSNETS\u201915)","author":"Xuhang","unstructured":"Xuhang Ying et al. 2015a. Revisiting TV coverage estimation with measurement-based statistical interpolation . In Proceedings of the 7th International Conference on Communication Systems and Networks (COMSNETS\u201915) . IEEE. Xuhang Ying et al. 2015a. Revisiting TV coverage estimation with measurement-based statistical interpolation. In Proceedings of the 7th International Conference on Communication Systems and Networks (COMSNETS\u201915). IEEE."},{"key":"e_1_2_1_45_1","doi-asserted-by":"publisher","DOI":"10.1109\/DySPAN.2015.7343932"},{"key":"e_1_2_1_46_1","doi-asserted-by":"publisher","DOI":"10.1145\/2500423.2500439"},{"key":"e_1_2_1_47_1","doi-asserted-by":"publisher","DOI":"10.1109\/TCCN.2017.2701812"},{"key":"e_1_2_1_48_1","volume-title":"Proceedings of the IEEE Conference on Computer Communications (INFOCOM\u201915)","author":"Zhang J.","unstructured":"J. Zhang , W. Zhang , M. Chen , and Z. Wang . 2015. WINET: Indoor white space network design . In Proceedings of the IEEE Conference on Computer Communications (INFOCOM\u201915) . 630--638. J. Zhang, W. Zhang, M. Chen, and Z. Wang. 2015. WINET: Indoor white space network design. 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