{"id":"https://openalex.org/W4414908729","doi":"https://doi.org/10.1109/tcomm.2025.3618668","title":"Near-Field Hierarchical Beam Training for Reconfigurable Holographic Surfaces","display_name":"Near-Field Hierarchical Beam Training for Reconfigurable Holographic Surfaces","publication_year":2025,"publication_date":"2025-10-07","ids":{"openalex":"https://openalex.org/W4414908729","doi":"https://doi.org/10.1109/tcomm.2025.3618668"},"language":"en","primary_location":{"id":"doi:10.1109/tcomm.2025.3618668","is_oa":false,"landing_page_url":"https://doi.org/10.1109/tcomm.2025.3618668","pdf_url":null,"source":{"id":"https://openalex.org/S196647941","display_name":"IEEE Transactions on Communications","issn_l":"0090-6778","issn":["0090-6778","1558-0857"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310316002","host_organization_name":"IEEE Communications Society","host_organization_lineage":["https://openalex.org/P4310316002","https://openalex.org/P4310319808"],"host_organization_lineage_names":["IEEE Communications Society","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 Communications","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":true,"oa_status":"green","oa_url":"https://eprints.soton.ac.uk/506380/1/main.pdf","any_repository_has_fulltext":true},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5108999788","display_name":"Y. F. Dong","orcid":"https://orcid.org/0009-0003-2871-8479"},"institutions":[{"id":"https://openalex.org/I43439940","display_name":"University of Southampton","ror":"https://ror.org/01ryk1543","country_code":"GB","type":"education","lineage":["https://openalex.org/I43439940"]}],"countries":["GB"],"is_corresponding":false,"raw_author_name":"Yinuo Dong","raw_affiliation_strings":["School of Electronics and Computer Science, University of Southampton, Southampton, U.K","School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom"],"raw_orcid":"https://orcid.org/0009-0003-2871-8479","affiliations":[{"raw_affiliation_string":"School of Electronics and Computer Science, University of Southampton, Southampton, U.K","institution_ids":["https://openalex.org/I43439940"]},{"raw_affiliation_string":"School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom","institution_ids":["https://openalex.org/I43439940"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5004654557","display_name":"Qingchao Li","orcid":"https://orcid.org/0000-0003-4928-334X"},"institutions":[{"id":"https://openalex.org/I43439940","display_name":"University of Southampton","ror":"https://ror.org/01ryk1543","country_code":"GB","type":"education","lineage":["https://openalex.org/I43439940"]}],"countries":["GB"],"is_corresponding":false,"raw_author_name":"Qingchao Li","raw_affiliation_strings":["School of Electronics and Computer Science, University of Southampton, Southampton, U.K","School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom"],"raw_orcid":"https://orcid.org/0000-0003-4928-334X","affiliations":[{"raw_affiliation_string":"School of Electronics and Computer Science, University of Southampton, Southampton, U.K","institution_ids":["https://openalex.org/I43439940"]},{"raw_affiliation_string":"School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom","institution_ids":["https://openalex.org/I43439940"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5041481409","display_name":"Soon Xin Ng","orcid":"https://orcid.org/0000-0002-0930-7194"},"institutions":[{"id":"https://openalex.org/I43439940","display_name":"University of Southampton","ror":"https://ror.org/01ryk1543","country_code":"GB","type":"education","lineage":["https://openalex.org/I43439940"]}],"countries":["GB"],"is_corresponding":false,"raw_author_name":"Soon Xin Ng","raw_affiliation_strings":["School of Electronics and Computer Science, University of Southampton, Southampton, U.K","School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom"],"raw_orcid":"https://orcid.org/0000-0002-0930-7194","affiliations":[{"raw_affiliation_string":"School of Electronics and Computer Science, University of Southampton, Southampton, U.K","institution_ids":["https://openalex.org/I43439940"]},{"raw_affiliation_string":"School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom","institution_ids":["https://openalex.org/I43439940"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5016934590","display_name":"Mohammed El\u2010Hajjar","orcid":"https://orcid.org/0000-0002-7987-1401"},"institutions":[{"id":"https://openalex.org/I43439940","display_name":"University of Southampton","ror":"https://ror.org/01ryk1543","country_code":"GB","type":"education","lineage":["https://openalex.org/I43439940"]}],"countries":["GB"],"is_corresponding":false,"raw_author_name":"Mohammed El-Hajjar","raw_affiliation_strings":["School of Electronics and Computer Science, University of Southampton, Southampton, U.K","School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom"],"raw_orcid":"https://orcid.org/0000-0002-7987-1401","affiliations":[{"raw_affiliation_string":"School of Electronics and Computer Science, University of Southampton, Southampton, U.K","institution_ids":["https://openalex.org/I43439940"]},{"raw_affiliation_string":"School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom","institution_ids":["https://openalex.org/I43439940"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":1,"corresponding_author_ids":[],"corresponding_institution_ids":["https://openalex.org/I43439940"],"apc_list":null,"apc_paid":null,"fwci":0.0,"has_fulltext":true,"cited_by_count":0,"citation_normalized_percentile":{"value":0.33517181,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":null,"biblio":{"volume":"73","issue":"12","first_page":"13876","last_page":"13890"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11383","display_name":"Advanced Antenna and Metasurface Technologies","score":0.9975000023841858,"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"}},"topics":[{"id":"https://openalex.org/T11383","display_name":"Advanced Antenna and Metasurface Technologies","score":0.9975000023841858,"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/T11946","display_name":"Antenna Design and Optimization","score":0.9940000176429749,"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/T10069","display_name":"Antenna Design and Analysis","score":0.9692999720573425,"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"}}],"keywords":[{"id":"https://openalex.org/keywords/orthogonality","display_name":"Orthogonality","score":0.73580002784729},{"id":"https://openalex.org/keywords/robustness","display_name":"Robustness (evolution)","score":0.6093999743461609},{"id":"https://openalex.org/keywords/holography","display_name":"Holography","score":0.5507000088691711},{"id":"https://openalex.org/keywords/beam","display_name":"Beam (structure)","score":0.5221999883651733},{"id":"https://openalex.org/keywords/reconfigurable-antenna","display_name":"Reconfigurable antenna","score":0.511900007724762},{"id":"https://openalex.org/keywords/channel","display_name":"Channel (broadcasting)","score":0.4916999936103821},{"id":"https://openalex.org/keywords/computer-generated-holography","display_name":"Computer-generated holography","score":0.3935999870300293},{"id":"https://openalex.org/keywords/aperture","display_name":"Aperture (computer memory)","score":0.3815999925136566}],"concepts":[{"id":"https://openalex.org/C17137986","wikidata":"https://www.wikidata.org/wiki/Q215067","display_name":"Orthogonality","level":2,"score":0.73580002784729},{"id":"https://openalex.org/C63479239","wikidata":"https://www.wikidata.org/wiki/Q7353546","display_name":"Robustness (evolution)","level":3,"score":0.6093999743461609},{"id":"https://openalex.org/C187590223","wikidata":"https://www.wikidata.org/wiki/Q527628","display_name":"Holography","level":2,"score":0.5507000088691711},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.5246999859809875},{"id":"https://openalex.org/C168834538","wikidata":"https://www.wikidata.org/wiki/Q3705329","display_name":"Beam (structure)","level":2,"score":0.5221999883651733},{"id":"https://openalex.org/C131369404","wikidata":"https://www.wikidata.org/wiki/Q7554278","display_name":"Reconfigurable antenna","level":5,"score":0.511900007724762},{"id":"https://openalex.org/C24326235","wikidata":"https://www.wikidata.org/wiki/Q126095","display_name":"Electronic engineering","level":1,"score":0.5077999830245972},{"id":"https://openalex.org/C127162648","wikidata":"https://www.wikidata.org/wiki/Q16858953","display_name":"Channel (broadcasting)","level":2,"score":0.4916999936103821},{"id":"https://openalex.org/C2778045333","wikidata":"https://www.wikidata.org/wiki/Q5157395","display_name":"Computer-generated holography","level":3,"score":0.3935999870300293},{"id":"https://openalex.org/C78336883","wikidata":"https://www.wikidata.org/wiki/Q4779385","display_name":"Aperture (computer memory)","level":2,"score":0.3815999925136566},{"id":"https://openalex.org/C148063708","wikidata":"https://www.wikidata.org/wiki/Q5072511","display_name":"Channel state information","level":3,"score":0.34369999170303345},{"id":"https://openalex.org/C9390403","wikidata":"https://www.wikidata.org/wiki/Q3966","display_name":"Computer hardware","level":1,"score":0.33899998664855957},{"id":"https://openalex.org/C143635782","wikidata":"https://www.wikidata.org/wiki/Q1187868","display_name":"Smart antenna","level":4,"score":0.3303000032901764},{"id":"https://openalex.org/C127413603","wikidata":"https://www.wikidata.org/wiki/Q11023","display_name":"Engineering","level":0,"score":0.32249999046325684},{"id":"https://openalex.org/C143148639","wikidata":"https://www.wikidata.org/wiki/Q4876192","display_name":"Beam steering","level":3,"score":0.3197999894618988},{"id":"https://openalex.org/C113775141","wikidata":"https://www.wikidata.org/wiki/Q428691","display_name":"Computer engineering","level":1,"score":0.3000999987125397},{"id":"https://openalex.org/C2776257435","wikidata":"https://www.wikidata.org/wiki/Q1576430","display_name":"Bandwidth (computing)","level":2,"score":0.29820001125335693},{"id":"https://openalex.org/C26517878","wikidata":"https://www.wikidata.org/wiki/Q228039","display_name":"Key (lock)","level":2,"score":0.2953999936580658},{"id":"https://openalex.org/C2777211547","wikidata":"https://www.wikidata.org/wiki/Q17141490","display_name":"Training (meteorology)","level":2,"score":0.29490000009536743},{"id":"https://openalex.org/C19889080","wikidata":"https://www.wikidata.org/wiki/Q2835852","display_name":"Beam search","level":3,"score":0.2946000099182129},{"id":"https://openalex.org/C131584629","wikidata":"https://www.wikidata.org/wiki/Q4308705","display_name":"Coupling (piping)","level":2,"score":0.2888999879360199},{"id":"https://openalex.org/C142962650","wikidata":"https://www.wikidata.org/wiki/Q240838","display_name":"Reconfigurable computing","level":3,"score":0.2635999917984009},{"id":"https://openalex.org/C2778915421","wikidata":"https://www.wikidata.org/wiki/Q3643177","display_name":"Performance improvement","level":2,"score":0.2572999894618988},{"id":"https://openalex.org/C48372109","wikidata":"https://www.wikidata.org/wiki/Q3913","display_name":"Binary number","level":2,"score":0.25519999861717224},{"id":"https://openalex.org/C62191587","wikidata":"https://www.wikidata.org/wiki/Q4771249","display_name":"Antenna array","level":3,"score":0.2524999976158142}],"mesh":[],"locations_count":2,"locations":[{"id":"doi:10.1109/tcomm.2025.3618668","is_oa":false,"landing_page_url":"https://doi.org/10.1109/tcomm.2025.3618668","pdf_url":null,"source":{"id":"https://openalex.org/S196647941","display_name":"IEEE Transactions on Communications","issn_l":"0090-6778","issn":["0090-6778","1558-0857"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310316002","host_organization_name":"IEEE Communications Society","host_organization_lineage":["https://openalex.org/P4310316002","https://openalex.org/P4310319808"],"host_organization_lineage_names":["IEEE Communications Society","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 Communications","raw_type":"journal-article"},{"id":"pmh:oai:eprints.soton.ac.uk:506380","is_oa":true,"landing_page_url":"http://doi.org/10.1109/TCOMM.2025.3618668>).","pdf_url":"https://eprints.soton.ac.uk/506380/1/main.pdf","source":{"id":"https://openalex.org/S4306401019","display_name":"ePrints Soton (University of Southampton)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I43439940","host_organization_name":"University of Southampton","host_organization_lineage":["https://openalex.org/I43439940"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":null,"raw_type":"Article"}],"best_oa_location":{"id":"pmh:oai:eprints.soton.ac.uk:506380","is_oa":true,"landing_page_url":"http://doi.org/10.1109/TCOMM.2025.3618668>).","pdf_url":"https://eprints.soton.ac.uk/506380/1/main.pdf","source":{"id":"https://openalex.org/S4306401019","display_name":"ePrints Soton (University of Southampton)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I43439940","host_organization_name":"University of Southampton","host_organization_lineage":["https://openalex.org/I43439940"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":null,"raw_type":"Article"},"sustainable_development_goals":[],"awards":[],"funders":[],"has_content":{"grobid_xml":true,"pdf":true},"content_urls":{"pdf":"https://content.openalex.org/works/W4414908729.pdf","grobid_xml":"https://content.openalex.org/works/W4414908729.grobid-xml"},"referenced_works_count":0,"referenced_works":[],"related_works":[],"abstract_inverted_index":{"Reconfigurable":[0],"holographic":[1],"surfaces":[2,192],"(RHS)":[3],"are":[4,79],"expected":[5],"to":[6,124,164],"play":[7],"a":[8,33,118,125],"key":[9],"role":[10],"in":[11,19,200],"future":[12],"mobile":[13],"networks.":[14],"However,":[15],"the":[16,60,110,174,201],"substantial":[17],"increase":[18],"antenna":[20],"aperture":[21],"and":[22,51,76,99,139,155],"operating":[23],"frequency":[24],"brings":[25],"new":[26],"challenges":[27],"for":[28,42,136,197],"near-field":[29,34,50,178],"communication.":[30],"We":[31],"propose":[32,92],"multi-user":[35],"3D":[36],"hierarchical":[37,61,111],"beam":[38,62,112,120,179,195],"training":[39,63,113,121],"scheme":[40,64],"tailored":[41,123],"RHS-based":[43],"multi-input":[44],"multi-output":[45],"(MIMO)":[46],"systems,":[47],"supporting":[48],"both":[49,137],"far-field":[52],"user":[53],"deployment,":[54],"while":[55],"considering":[56],"hardware":[57,142,154],"constraints.":[58],"Since":[59],"involves":[65],"activating":[66],"varying":[67],"numbers":[68],"of":[69,166,177],"transmitting":[70],"elements":[71,78],"at":[72,206],"each":[73],"search":[74],"layer,":[75],"RHS":[77,105,145,184],"densely":[80],"packed,":[81],"significant":[82],"mutual":[83],"coupling":[84],"effects":[85],"may":[86],"arise.":[87],"To":[88],"mitigate":[89],"this,":[90],"we":[91,116,171],"two":[93],"element":[94,106],"activation":[95,98,101],"strategies:":[96],"centered":[97],"sparse":[100],"based":[102],"on":[103,144],"different":[104,183,207],"positioning":[107],"patterns":[108],"within":[109],"framework.":[114],"Furthermore,":[115],"design":[117],"practical":[119],"approach":[122],"hybrid":[126],"digital\u2013holographic":[127],"architecture,":[128],"optimized":[129],"through":[130],"an":[131],"alternating":[132],"algorithm":[133],"that":[134,165,190],"accounts":[135],"binary":[138],"coupled":[140],"amplitude-phase":[141],"constraints":[143],"meta-elements.":[146],"Simulation":[147],"results":[148,188],"demonstrate":[149],"strong":[150],"robustness":[151],"under":[152,182],"various":[153],"channel":[156],"state":[157],"information":[158],"(CSI)":[159],"imperfections,":[160],"achieving":[161],"performance":[162],"close":[163],"fully":[167],"digital":[168],"systems.":[169],"Finally,":[170],"further":[172],"analyse":[173],"asymptotic":[175],"orthogonality":[176,196],"focusing":[180],"vectors":[181],"surface":[185],"geometries.":[186],"The":[187],"show":[189],"rectangular":[191],"offer":[193],"superior":[194],"beams":[198],"steered":[199],"same":[202],"direction":[203],"but":[204],"located":[205],"distances.":[208]},"counts_by_year":[],"updated_date":"2026-07-02T09:51:11.867554","created_date":"2025-10-10T00:00:00"}