{"id":"https://openalex.org/W3199369452","doi":"https://doi.org/10.1109/lwc.2021.3112781","title":"Small-Scale Spatial-Temporal Correlation and Degrees of Freedom for Reconfigurable Intelligent Surfaces","display_name":"Small-Scale Spatial-Temporal Correlation and Degrees of Freedom for Reconfigurable Intelligent Surfaces","publication_year":2021,"publication_date":"2021-09-15","ids":{"openalex":"https://openalex.org/W3199369452","doi":"https://doi.org/10.1109/lwc.2021.3112781","mag":"3199369452"},"language":"en","primary_location":{"id":"doi:10.1109/lwc.2021.3112781","is_oa":false,"landing_page_url":"https://doi.org/10.1109/lwc.2021.3112781","pdf_url":null,"source":{"id":"https://openalex.org/S2500830676","display_name":"IEEE Wireless Communications Letters","issn_l":"2162-2337","issn":["2162-2337","2162-2345"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310319808","host_organization_name":"Institute of Electrical and Electronics Engineers","host_organization_lineage":["https://openalex.org/P4310319808"],"host_organization_lineage_names":["Institute of Electrical and Electronics Engineers"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"IEEE Wireless Communications Letters","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5014646698","display_name":"Shu Sun","orcid":"https://orcid.org/0000-0001-8655-3746"},"institutions":[{"id":"https://openalex.org/I1343180700","display_name":"Intel (United States)","ror":"https://ror.org/01ek73717","country_code":"US","type":"company","lineage":["https://openalex.org/I1343180700"]},{"id":"https://openalex.org/I183067930","display_name":"Shanghai Jiao Tong University","ror":"https://ror.org/0220qvk04","country_code":"CN","type":"education","lineage":["https://openalex.org/I183067930"]}],"countries":["CN","US"],"is_corresponding":true,"raw_author_name":"Shu Sun","raw_affiliation_strings":["Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai, China","Next Generation and Standards Group, Intel Corporation, Santa Clara, CA, USA"],"affiliations":[{"raw_affiliation_string":"Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai, China","institution_ids":["https://openalex.org/I183067930"]},{"raw_affiliation_string":"Next Generation and Standards Group, Intel Corporation, Santa Clara, CA, USA","institution_ids":["https://openalex.org/I1343180700"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5039169473","display_name":"Hangsong Yan","orcid":"https://orcid.org/0000-0002-0463-8058"},"institutions":[{"id":"https://openalex.org/I57206974","display_name":"New York University","ror":"https://ror.org/0190ak572","country_code":"US","type":"education","lineage":["https://openalex.org/I57206974"]}],"countries":["US"],"is_corresponding":false,"raw_author_name":"Hangsong Yan","raw_affiliation_strings":["NYU WIRELESS Research Center and Tandon School of Engineering, New York University, Brooklyn, NY, USA"],"affiliations":[{"raw_affiliation_string":"NYU WIRELESS Research Center and Tandon School of Engineering, New York University, Brooklyn, NY, USA","institution_ids":["https://openalex.org/I57206974"]}]}],"institutions":[],"countries_distinct_count":2,"institutions_distinct_count":2,"corresponding_author_ids":["https://openalex.org/A5014646698"],"corresponding_institution_ids":["https://openalex.org/I1343180700","https://openalex.org/I183067930"],"apc_list":null,"apc_paid":null,"fwci":1.8049,"has_fulltext":false,"cited_by_count":23,"citation_normalized_percentile":{"value":0.85203283,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":{"min":89,"max":99},"biblio":{"volume":"10","issue":"12","first_page":"2698","last_page":"2702"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11458","display_name":"Advanced Wireless Communication Technologies","score":0.9997000098228455,"subfield":{"id":"https://openalex.org/subfields/2208","display_name":"Electrical and Electronic Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T11458","display_name":"Advanced Wireless Communication Technologies","score":0.9997000098228455,"subfield":{"id":"https://openalex.org/subfields/2208","display_name":"Electrical and Electronic Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11383","display_name":"Advanced Antenna and Metasurface Technologies","score":0.998199999332428,"subfield":{"id":"https://openalex.org/subfields/2202","display_name":"Aerospace Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10245","display_name":"Metamaterials and Metasurfaces Applications","score":0.9980000257492065,"subfield":{"id":"https://openalex.org/subfields/2504","display_name":"Electronic, Optical and Magnetic Materials"},"field":{"id":"https://openalex.org/fields/25","display_name":"Materials Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/spatial-correlation","display_name":"Spatial correlation","score":0.8100547790527344},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.6285443305969238},{"id":"https://openalex.org/keywords/wireless","display_name":"Wireless","score":0.5385410189628601},{"id":"https://openalex.org/keywords/scale","display_name":"Scale (ratio)","score":0.515228807926178},{"id":"https://openalex.org/keywords/correlation-function","display_name":"Correlation function (quantum field theory)","score":0.4766993224620819},{"id":"https://openalex.org/keywords/correlation","display_name":"Correlation","score":0.4683353900909424},{"id":"https://openalex.org/keywords/degrees-of-freedom","display_name":"Degrees of freedom (physics and chemistry)","score":0.4617358446121216},{"id":"https://openalex.org/keywords/electronic-engineering","display_name":"Electronic engineering","score":0.3319966793060303},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.22688663005828857},{"id":"https://openalex.org/keywords/telecommunications","display_name":"Telecommunications","score":0.18846452236175537},{"id":"https://openalex.org/keywords/spectral-density","display_name":"Spectral density","score":0.16630008816719055},{"id":"https://openalex.org/keywords/geometry","display_name":"Geometry","score":0.14986824989318848},{"id":"https://openalex.org/keywords/physics","display_name":"Physics","score":0.1460510790348053},{"id":"https://openalex.org/keywords/engineering","display_name":"Engineering","score":0.1387338936328888}],"concepts":[{"id":"https://openalex.org/C150060386","wikidata":"https://www.wikidata.org/wiki/Q7574054","display_name":"Spatial correlation","level":2,"score":0.8100547790527344},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.6285443305969238},{"id":"https://openalex.org/C555944384","wikidata":"https://www.wikidata.org/wiki/Q249","display_name":"Wireless","level":2,"score":0.5385410189628601},{"id":"https://openalex.org/C2778755073","wikidata":"https://www.wikidata.org/wiki/Q10858537","display_name":"Scale (ratio)","level":2,"score":0.515228807926178},{"id":"https://openalex.org/C53622274","wikidata":"https://www.wikidata.org/wiki/Q2496679","display_name":"Correlation function (quantum field theory)","level":3,"score":0.4766993224620819},{"id":"https://openalex.org/C117220453","wikidata":"https://www.wikidata.org/wiki/Q5172842","display_name":"Correlation","level":2,"score":0.4683353900909424},{"id":"https://openalex.org/C208081375","wikidata":"https://www.wikidata.org/wiki/Q274502","display_name":"Degrees of freedom (physics and chemistry)","level":2,"score":0.4617358446121216},{"id":"https://openalex.org/C24326235","wikidata":"https://www.wikidata.org/wiki/Q126095","display_name":"Electronic engineering","level":1,"score":0.3319966793060303},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.22688663005828857},{"id":"https://openalex.org/C76155785","wikidata":"https://www.wikidata.org/wiki/Q418","display_name":"Telecommunications","level":1,"score":0.18846452236175537},{"id":"https://openalex.org/C168110828","wikidata":"https://www.wikidata.org/wiki/Q1331626","display_name":"Spectral density","level":2,"score":0.16630008816719055},{"id":"https://openalex.org/C2524010","wikidata":"https://www.wikidata.org/wiki/Q8087","display_name":"Geometry","level":1,"score":0.14986824989318848},{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.1460510790348053},{"id":"https://openalex.org/C127413603","wikidata":"https://www.wikidata.org/wiki/Q11023","display_name":"Engineering","level":0,"score":0.1387338936328888},{"id":"https://openalex.org/C62520636","wikidata":"https://www.wikidata.org/wiki/Q944","display_name":"Quantum mechanics","level":1,"score":0.0}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1109/lwc.2021.3112781","is_oa":false,"landing_page_url":"https://doi.org/10.1109/lwc.2021.3112781","pdf_url":null,"source":{"id":"https://openalex.org/S2500830676","display_name":"IEEE Wireless Communications Letters","issn_l":"2162-2337","issn":["2162-2337","2162-2345"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310319808","host_organization_name":"Institute of Electrical and Electronics Engineers","host_organization_lineage":["https://openalex.org/P4310319808"],"host_organization_lineage_names":["Institute of Electrical and Electronics Engineers"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"IEEE Wireless Communications Letters","raw_type":"journal-article"}],"best_oa_location":null,"sustainable_development_goals":[{"id":"https://metadata.un.org/sdg/16","score":0.8100000023841858,"display_name":"Peace, Justice and strong institutions"}],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":14,"referenced_works":["https://openalex.org/W2012215229","https://openalex.org/W2118761136","https://openalex.org/W2147601077","https://openalex.org/W2152434680","https://openalex.org/W2604883088","https://openalex.org/W2808499605","https://openalex.org/W3034737405","https://openalex.org/W3041653465","https://openalex.org/W3084194173","https://openalex.org/W3113261730","https://openalex.org/W3116798772","https://openalex.org/W3117633996","https://openalex.org/W3153831106","https://openalex.org/W3167603521"],"related_works":["https://openalex.org/W1988032185","https://openalex.org/W2367415877","https://openalex.org/W2103183736","https://openalex.org/W2365283995","https://openalex.org/W2898021863","https://openalex.org/W4320029439","https://openalex.org/W2944975215","https://openalex.org/W2146539362","https://openalex.org/W1563436776","https://openalex.org/W1995086486"],"abstract_inverted_index":{"The":[0,124],"reconfigurable":[1],"intelligent":[2],"surface":[3],"(RIS)":[4],"is":[5,19,62,99,105],"an":[6,39,50,87,102],"emerging":[7],"promising":[8],"candidate":[9],"technology":[10],"for":[11,49,112],"future":[12],"wireless":[13,52],"networks,":[14],"where":[15],"the":[16,31,36,46,79,92,109,129],"element":[17,118],"spacing":[18,119],"usually":[20],"of":[21,95,132],"sub-wavelength.":[22],"Only":[23],"limited":[24],"knowledge,":[25],"however,":[26],"has":[27],"been":[28],"gained":[29],"about":[30],"spatial-temporal":[32,47,59],"correlation":[33,48,60,81],"behavior":[34],"among":[35],"elements":[37],"in":[38],"RIS.":[40],"In":[41],"this":[42],"letter,":[43],"we":[44],"investigate":[45],"RIS-enabled":[51],"communication":[53],"system.":[54],"Specifically,":[55],"a":[56,72,83],"joint":[57],"small-scale":[58],"model":[61],"derived":[63],"under":[64],"isotropic":[65],"scattering,":[66],"which":[67],"can":[68],"be":[69],"represented":[70],"by":[71],"four-dimensional":[73],"sinc":[74],"function.":[75],"Furthermore,":[76],"based":[77],"upon":[78],"spatial-only":[80],"at":[82],"certain":[84],"time":[85],"instant,":[86],"essential":[88],"RIS":[89],"property":[90],"\u2013":[91,98],"spatial":[93,110],"degrees":[94],"freedom":[96],"(DoF)":[97],"revisited,":[100],"and":[101,120],"analytical":[103],"expression":[104],"propounded":[106],"to":[107,128],"characterize":[108],"DoF":[111],"RISs":[113],"with":[114],"realistic":[115],"hence":[116],"non-infinitesimal":[117],"finite":[121],"aperture":[122],"sizes.":[123],"results":[125],"are":[126],"vital":[127],"accurate":[130],"evaluation":[131],"various":[133],"system":[134],"performance":[135],"metrics.":[136]},"counts_by_year":[{"year":2025,"cited_by_count":5},{"year":2024,"cited_by_count":4},{"year":2023,"cited_by_count":8},{"year":2022,"cited_by_count":5},{"year":2021,"cited_by_count":1}],"updated_date":"2025-11-06T03:46:38.306776","created_date":"2025-10-10T00:00:00"}