{"id":"https://openalex.org/W4415626599","doi":"https://doi.org/10.1109/twc.2025.3624235","title":"Piecewise Beam Training and Channel Estimation for RIS-Aided Near-Field Communications","display_name":"Piecewise Beam Training and Channel Estimation for RIS-Aided Near-Field Communications","publication_year":2025,"publication_date":"2025-10-28","ids":{"openalex":"https://openalex.org/W4415626599","doi":"https://doi.org/10.1109/twc.2025.3624235"},"language":null,"primary_location":{"id":"doi:10.1109/twc.2025.3624235","is_oa":false,"landing_page_url":"https://doi.org/10.1109/twc.2025.3624235","pdf_url":null,"source":{"id":"https://openalex.org/S63459445","display_name":"IEEE Transactions on Wireless Communications","issn_l":"1536-1276","issn":["1536-1276","1558-2248"],"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 Transactions on Wireless Communications","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/A5068965339","display_name":"Jeongjae Lee","orcid":"https://orcid.org/0009-0003-8149-2149"},"institutions":[{"id":"https://openalex.org/I4575257","display_name":"Hanyang University","ror":"https://ror.org/046865y68","country_code":"KR","type":"education","lineage":["https://openalex.org/I4575257"]}],"countries":["KR"],"is_corresponding":true,"raw_author_name":"Jeongjae Lee","raw_affiliation_strings":["Department of Electronic Engineering, Hanyang University, Seoul, South Korea","Department of Electronic Engineering, Hanyang University, Seoul, Korea"],"affiliations":[{"raw_affiliation_string":"Department of Electronic Engineering, Hanyang University, Seoul, South Korea","institution_ids":["https://openalex.org/I4575257"]},{"raw_affiliation_string":"Department of Electronic Engineering, Hanyang University, Seoul, Korea","institution_ids":["https://openalex.org/I4575257"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5084652371","display_name":"Song\u2010Nam Hong","orcid":"https://orcid.org/0000-0002-9535-2521"},"institutions":[{"id":"https://openalex.org/I4575257","display_name":"Hanyang University","ror":"https://ror.org/046865y68","country_code":"KR","type":"education","lineage":["https://openalex.org/I4575257"]}],"countries":["KR"],"is_corresponding":false,"raw_author_name":"Songnam Hong","raw_affiliation_strings":["Department of Electronic Engineering, Hanyang University, Seoul, South Korea","Department of Electronic Engineering, Hanyang University, Seoul, Korea"],"affiliations":[{"raw_affiliation_string":"Department of Electronic Engineering, Hanyang University, Seoul, South Korea","institution_ids":["https://openalex.org/I4575257"]},{"raw_affiliation_string":"Department of Electronic Engineering, Hanyang University, Seoul, Korea","institution_ids":["https://openalex.org/I4575257"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":2,"corresponding_author_ids":["https://openalex.org/A5068965339"],"corresponding_institution_ids":["https://openalex.org/I4575257"],"apc_list":null,"apc_paid":null,"fwci":0.7181,"has_fulltext":false,"cited_by_count":1,"citation_normalized_percentile":{"value":0.77717601,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":{"min":96,"max":99},"biblio":{"volume":"25","issue":null,"first_page":"6270","last_page":"6283"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11458","display_name":"Advanced Wireless Communication Technologies","score":0.9921000003814697,"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":0.9921000003814697,"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":0.0020000000949949026,"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/T11192","display_name":"Underwater Vehicles and Communication Systems","score":0.000699999975040555,"subfield":{"id":"https://openalex.org/subfields/2212","display_name":"Ocean Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/channel","display_name":"Channel (broadcasting)","score":0.8252999782562256},{"id":"https://openalex.org/keywords/overhead","display_name":"Overhead (engineering)","score":0.618399977684021},{"id":"https://openalex.org/keywords/piecewise","display_name":"Piecewise","score":0.6083999872207642},{"id":"https://openalex.org/keywords/coherence","display_name":"Coherence (philosophical gambling strategy)","score":0.5989999771118164},{"id":"https://openalex.org/keywords/computational-complexity-theory","display_name":"Computational complexity theory","score":0.5467000007629395},{"id":"https://openalex.org/keywords/coherence-time","display_name":"Coherence time","score":0.46619999408721924},{"id":"https://openalex.org/keywords/block","display_name":"Block (permutation group theory)","score":0.4293999969959259},{"id":"https://openalex.org/keywords/orthogonal-frequency-division-multiplexing","display_name":"Orthogonal frequency-division multiplexing","score":0.37369999289512634}],"concepts":[{"id":"https://openalex.org/C127162648","wikidata":"https://www.wikidata.org/wiki/Q16858953","display_name":"Channel (broadcasting)","level":2,"score":0.8252999782562256},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.7443000078201294},{"id":"https://openalex.org/C2779960059","wikidata":"https://www.wikidata.org/wiki/Q7113681","display_name":"Overhead (engineering)","level":2,"score":0.618399977684021},{"id":"https://openalex.org/C164660894","wikidata":"https://www.wikidata.org/wiki/Q2037833","display_name":"Piecewise","level":2,"score":0.6083999872207642},{"id":"https://openalex.org/C2781181686","wikidata":"https://www.wikidata.org/wiki/Q4226068","display_name":"Coherence (philosophical gambling strategy)","level":2,"score":0.5989999771118164},{"id":"https://openalex.org/C179799912","wikidata":"https://www.wikidata.org/wiki/Q205084","display_name":"Computational complexity theory","level":2,"score":0.5467000007629395},{"id":"https://openalex.org/C47091857","wikidata":"https://www.wikidata.org/wiki/Q4118612","display_name":"Coherence time","level":3,"score":0.46619999408721924},{"id":"https://openalex.org/C2777210771","wikidata":"https://www.wikidata.org/wiki/Q4927124","display_name":"Block (permutation group theory)","level":2,"score":0.4293999969959259},{"id":"https://openalex.org/C11413529","wikidata":"https://www.wikidata.org/wiki/Q8366","display_name":"Algorithm","level":1,"score":0.42879998683929443},{"id":"https://openalex.org/C40409654","wikidata":"https://www.wikidata.org/wiki/Q375889","display_name":"Orthogonal frequency-division multiplexing","level":3,"score":0.37369999289512634},{"id":"https://openalex.org/C167928553","wikidata":"https://www.wikidata.org/wiki/Q1376021","display_name":"Estimation theory","level":2,"score":0.3725000023841858},{"id":"https://openalex.org/C24326235","wikidata":"https://www.wikidata.org/wiki/Q126095","display_name":"Electronic engineering","level":1,"score":0.3650999963283539},{"id":"https://openalex.org/C168834538","wikidata":"https://www.wikidata.org/wiki/Q3705329","display_name":"Beam (structure)","level":2,"score":0.32760000228881836},{"id":"https://openalex.org/C79403827","wikidata":"https://www.wikidata.org/wiki/Q3988","display_name":"Real-time computing","level":1,"score":0.30140000581741333},{"id":"https://openalex.org/C47798520","wikidata":"https://www.wikidata.org/wiki/Q190157","display_name":"Transmitter","level":3,"score":0.29739999771118164},{"id":"https://openalex.org/C160562895","wikidata":"https://www.wikidata.org/wiki/Q7239557","display_name":"Precoding","level":4,"score":0.29120001196861267},{"id":"https://openalex.org/C96250715","wikidata":"https://www.wikidata.org/wiki/Q965330","display_name":"Estimation","level":2,"score":0.28130000829696655},{"id":"https://openalex.org/C126255220","wikidata":"https://www.wikidata.org/wiki/Q141495","display_name":"Mathematical optimization","level":1,"score":0.28119999170303345},{"id":"https://openalex.org/C104267543","wikidata":"https://www.wikidata.org/wiki/Q208163","display_name":"Signal processing","level":3,"score":0.2770000100135803},{"id":"https://openalex.org/C555944384","wikidata":"https://www.wikidata.org/wiki/Q249","display_name":"Wireless","level":2,"score":0.27000001072883606},{"id":"https://openalex.org/C113775141","wikidata":"https://www.wikidata.org/wiki/Q428691","display_name":"Computer engineering","level":1,"score":0.26010000705718994},{"id":"https://openalex.org/C189950617","wikidata":"https://www.wikidata.org/wiki/Q937228","display_name":"Property (philosophy)","level":2,"score":0.2563000023365021}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1109/twc.2025.3624235","is_oa":false,"landing_page_url":"https://doi.org/10.1109/twc.2025.3624235","pdf_url":null,"source":{"id":"https://openalex.org/S63459445","display_name":"IEEE Transactions on Wireless Communications","issn_l":"1536-1276","issn":["1536-1276","1558-2248"],"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 Transactions on Wireless Communications","raw_type":"journal-article"}],"best_oa_location":null,"sustainable_development_goals":[],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":41,"referenced_works":["https://openalex.org/W1977260461","https://openalex.org/W1997834106","https://openalex.org/W2074913070","https://openalex.org/W2104770042","https://openalex.org/W2145245010","https://openalex.org/W2248823781","https://openalex.org/W2345217022","https://openalex.org/W2792273065","https://openalex.org/W2807133510","https://openalex.org/W3002159761","https://openalex.org/W3043220753","https://openalex.org/W3072069827","https://openalex.org/W3129486236","https://openalex.org/W3154003282","https://openalex.org/W3176625087","https://openalex.org/W3203630573","https://openalex.org/W4205204962","https://openalex.org/W4226370247","https://openalex.org/W4312688996","https://openalex.org/W4312763750","https://openalex.org/W4320018468","https://openalex.org/W4321770460","https://openalex.org/W4322576964","https://openalex.org/W4360596735","https://openalex.org/W4360897390","https://openalex.org/W4380839009","https://openalex.org/W4385517018","https://openalex.org/W4389799491","https://openalex.org/W4390204381","https://openalex.org/W4390577869","https://openalex.org/W4394586155","https://openalex.org/W4394744873","https://openalex.org/W4394811136","https://openalex.org/W4396542228","https://openalex.org/W4399118807","https://openalex.org/W4402124977","https://openalex.org/W4402187313","https://openalex.org/W4403635747","https://openalex.org/W4407948898","https://openalex.org/W4408017156","https://openalex.org/W4408017173"],"related_works":[],"abstract_inverted_index":{"In":[0],"this":[1,40],"paper,":[2],"we":[3,42,123],"investigate":[4],"the":[5,30,51,57,63,79,90,96,101,107,112,137,140],"channel":[6,18,46,61,85,110,150,165],"estimation":[7,19,47,151],"challenge":[8],"in":[9,156],"reconfigurable":[10],"intelligent":[11],"surface":[12],"(RIS)-aided":[13],"near-field":[14],"communication":[15],"systems.":[16],"Current":[17],"techniques":[20],"require":[21],"substantial":[22],"pilot":[23,157],"overhead":[24,158],"and":[25,62,100,144,159],"computational":[26,160],"complexity,":[27],"especially":[28],"when":[29],"number":[31],"of":[32,55,92,139],"RIS":[33,142],"elements":[34],"is":[35],"extremely":[36],"large.":[37],"To":[38],"address":[39],"issue,":[41],"introduce":[43],"a":[44,68,93],"two-timescale":[45],"strategy":[48],"that":[49,148],"leverages":[50],"asymmetric":[52],"coherence":[53,81],"times":[54],"both":[56],"RIS-base":[58],"station":[59],"(BS)":[60],"User-RIS":[64],"channel.":[65,104],"We":[66,134],"derive":[67],"time-scaling":[69],"property":[70],"indicating":[71],"that,":[72],"for":[73,128],"any":[74],"two":[75],"effective":[76,84,98,103,109,132],"channels":[77],"within":[78],"longer":[80],"time,":[82],"one":[83],"can":[86],"be":[87],"represented":[88],"as":[89],"product":[91],"vector,":[94],"termed":[95],"small-timescale":[97,131],"channel,":[99],"other":[102],"By":[105],"integrating":[106],"estimated":[108],"from":[111,118],"initial":[113],"time":[114],"block":[115],"with":[116],"observations":[117],"our":[119,149],"piecewise":[120],"beam":[121],"training,":[122],"present":[124],"an":[125],"efficient":[126],"method":[127,152],"estimating":[129],"subsequent":[130],"channels.":[133],"theoretically":[135],"verify":[136],"efficacy":[138],"proposed":[141],"design":[143],"demonstrate,":[145],"through":[146],"simulations,":[147],"outperforms":[153],"existing":[154],"methods":[155],"complexity":[161],"across":[162],"various":[163],"realistic":[164],"models.":[166]},"counts_by_year":[{"year":2026,"cited_by_count":1}],"updated_date":"2026-04-02T15:55:50.835912","created_date":"2025-10-29T00:00:00"}
