{"id":"https://openalex.org/W4408323671","doi":"https://doi.org/10.1109/twc.2025.3546927","title":"Joint AP-UE Association and Precoding for SIM-Aided Cell-Free Massive MIMO Systems","display_name":"Joint AP-UE Association and Precoding for SIM-Aided Cell-Free Massive MIMO Systems","publication_year":2025,"publication_date":"2025-03-11","ids":{"openalex":"https://openalex.org/W4408323671","doi":"https://doi.org/10.1109/twc.2025.3546927"},"language":"en","primary_location":{"id":"doi:10.1109/twc.2025.3546927","is_oa":false,"landing_page_url":"https://doi.org/10.1109/twc.2025.3546927","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/A5033270201","display_name":"Enyu Shi","orcid":"https://orcid.org/0009-0007-9971-6066"},"institutions":[{"id":"https://openalex.org/I21193070","display_name":"Beijing Jiaotong University","ror":"https://ror.org/01yj56c84","country_code":"CN","type":"education","lineage":["https://openalex.org/I21193070"]}],"countries":["CN"],"is_corresponding":true,"raw_author_name":"Enyu Shi","raw_affiliation_strings":["State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China"],"raw_orcid":"https://orcid.org/0009-0007-9971-6066","affiliations":[{"raw_affiliation_string":"State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","institution_ids":["https://openalex.org/I21193070"]},{"raw_affiliation_string":"School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China","institution_ids":["https://openalex.org/I21193070"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5100612301","display_name":"Jiayi Zhang","orcid":"https://orcid.org/0000-0003-2434-4329"},"institutions":[{"id":"https://openalex.org/I21193070","display_name":"Beijing Jiaotong University","ror":"https://ror.org/01yj56c84","country_code":"CN","type":"education","lineage":["https://openalex.org/I21193070"]}],"countries":["CN"],"is_corresponding":false,"raw_author_name":"Jiayi Zhang","raw_affiliation_strings":["State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China"],"raw_orcid":"https://orcid.org/0000-0003-2434-4329","affiliations":[{"raw_affiliation_string":"State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","institution_ids":["https://openalex.org/I21193070"]},{"raw_affiliation_string":"School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China","institution_ids":["https://openalex.org/I21193070"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5052340806","display_name":"Jiancheng An","orcid":"https://orcid.org/0000-0003-2512-9989"},"institutions":[{"id":"https://openalex.org/I172675005","display_name":"Nanyang Technological University","ror":"https://ror.org/02e7b5302","country_code":"SG","type":"education","lineage":["https://openalex.org/I172675005"]}],"countries":["SG"],"is_corresponding":false,"raw_author_name":"Jiancheng An","raw_affiliation_strings":["School of Electrical and Electronics Engineering, Nanyang Technological University, Nanyang Ave, Singapore","School of Electrical and Electronics Engineering, Nanyang Technological University, Singapore"],"raw_orcid":"https://orcid.org/0000-0003-2512-9989","affiliations":[{"raw_affiliation_string":"School of Electrical and Electronics Engineering, Nanyang Technological University, Nanyang Ave, Singapore","institution_ids":["https://openalex.org/I172675005"]},{"raw_affiliation_string":"School of Electrical and Electronics Engineering, Nanyang Technological University, Singapore","institution_ids":["https://openalex.org/I172675005"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5013904006","display_name":"Guangyang Zhang","orcid":"https://orcid.org/0000-0001-6380-0468"},"institutions":[{"id":"https://openalex.org/I21193070","display_name":"Beijing Jiaotong University","ror":"https://ror.org/01yj56c84","country_code":"CN","type":"education","lineage":["https://openalex.org/I21193070"]}],"countries":["CN"],"is_corresponding":false,"raw_author_name":"Guangyang Zhang","raw_affiliation_strings":["State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China"],"raw_orcid":"https://orcid.org/0000-0001-6380-0468","affiliations":[{"raw_affiliation_string":"State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","institution_ids":["https://openalex.org/I21193070"]},{"raw_affiliation_string":"School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China","institution_ids":["https://openalex.org/I21193070"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5114444435","display_name":"Ziheng Liu","orcid":"https://orcid.org/0009-0000-5495-1619"},"institutions":[{"id":"https://openalex.org/I21193070","display_name":"Beijing Jiaotong University","ror":"https://ror.org/01yj56c84","country_code":"CN","type":"education","lineage":["https://openalex.org/I21193070"]}],"countries":["CN"],"is_corresponding":false,"raw_author_name":"Ziheng Liu","raw_affiliation_strings":["State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","institution_ids":["https://openalex.org/I21193070"]},{"raw_affiliation_string":"School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China","institution_ids":["https://openalex.org/I21193070"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5060020877","display_name":"Chau Yuen","orcid":"https://orcid.org/0000-0002-9307-2120"},"institutions":[{"id":"https://openalex.org/I172675005","display_name":"Nanyang Technological University","ror":"https://ror.org/02e7b5302","country_code":"SG","type":"education","lineage":["https://openalex.org/I172675005"]}],"countries":["SG"],"is_corresponding":false,"raw_author_name":"Chau Yuen","raw_affiliation_strings":["School of Electrical and Electronics Engineering, Nanyang Technological University, Nanyang Ave, Singapore","School of Electrical and Electronics Engineering, Nanyang Technological University, Singapore"],"raw_orcid":"https://orcid.org/0000-0002-9307-2120","affiliations":[{"raw_affiliation_string":"School of Electrical and Electronics Engineering, Nanyang Technological University, Nanyang Ave, Singapore","institution_ids":["https://openalex.org/I172675005"]},{"raw_affiliation_string":"School of Electrical and Electronics Engineering, Nanyang Technological University, Singapore","institution_ids":["https://openalex.org/I172675005"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5100620739","display_name":"Bo Ai","orcid":"https://orcid.org/0000-0001-6850-0595"},"institutions":[{"id":"https://openalex.org/I21193070","display_name":"Beijing Jiaotong University","ror":"https://ror.org/01yj56c84","country_code":"CN","type":"education","lineage":["https://openalex.org/I21193070"]}],"countries":["CN"],"is_corresponding":false,"raw_author_name":"Bo Ai","raw_affiliation_strings":["State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China"],"raw_orcid":"https://orcid.org/0000-0001-6850-0595","affiliations":[{"raw_affiliation_string":"State Key Laboratory of Advanced Rail Autonomous Operation and the School of Electronics and Information Engineering, Beijing Jiaotong University, Beijing, China","institution_ids":["https://openalex.org/I21193070"]},{"raw_affiliation_string":"School of Electronics and Information Engineering, State Key Laboratory of Advanced Rail Autonomous Operation, Beijing Jiaotong University, Beijing, P. R. China","institution_ids":["https://openalex.org/I21193070"]}]}],"institutions":[],"countries_distinct_count":2,"institutions_distinct_count":7,"corresponding_author_ids":["https://openalex.org/A5033270201"],"corresponding_institution_ids":["https://openalex.org/I21193070"],"apc_list":null,"apc_paid":null,"fwci":20.8997,"has_fulltext":false,"cited_by_count":32,"citation_normalized_percentile":{"value":0.99601232,"is_in_top_1_percent":true,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":99,"max":100},"biblio":{"volume":"24","issue":"6","first_page":"5352","last_page":"5367"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10148","display_name":"Advanced MIMO Systems Optimization","score":0.9995999932289124,"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/T10148","display_name":"Advanced MIMO Systems Optimization","score":0.9995999932289124,"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/T10187","display_name":"Radio Frequency Integrated Circuit Design","score":0.9973999857902527,"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/T10069","display_name":"Antenna Design and Analysis","score":0.9968000054359436,"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/precoding","display_name":"Precoding","score":0.8751058578491211},{"id":"https://openalex.org/keywords/mimo","display_name":"MIMO","score":0.6531856656074524},{"id":"https://openalex.org/keywords/joint","display_name":"Joint (building)","score":0.6305131912231445},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.6074005365371704},{"id":"https://openalex.org/keywords/zero-forcing-precoding","display_name":"Zero-forcing precoding","score":0.5802257061004639},{"id":"https://openalex.org/keywords/telecommunications","display_name":"Telecommunications","score":0.4080362617969513},{"id":"https://openalex.org/keywords/beamforming","display_name":"Beamforming","score":0.1482921540737152},{"id":"https://openalex.org/keywords/engineering","display_name":"Engineering","score":0.143986314535141}],"concepts":[{"id":"https://openalex.org/C160562895","wikidata":"https://www.wikidata.org/wiki/Q7239557","display_name":"Precoding","level":4,"score":0.8751058578491211},{"id":"https://openalex.org/C207987634","wikidata":"https://www.wikidata.org/wiki/Q176862","display_name":"MIMO","level":3,"score":0.6531856656074524},{"id":"https://openalex.org/C18555067","wikidata":"https://www.wikidata.org/wiki/Q8375051","display_name":"Joint (building)","level":2,"score":0.6305131912231445},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.6074005365371704},{"id":"https://openalex.org/C155437304","wikidata":"https://www.wikidata.org/wiki/Q8069444","display_name":"Zero-forcing precoding","level":5,"score":0.5802257061004639},{"id":"https://openalex.org/C76155785","wikidata":"https://www.wikidata.org/wiki/Q418","display_name":"Telecommunications","level":1,"score":0.4080362617969513},{"id":"https://openalex.org/C54197355","wikidata":"https://www.wikidata.org/wiki/Q5782992","display_name":"Beamforming","level":2,"score":0.1482921540737152},{"id":"https://openalex.org/C127413603","wikidata":"https://www.wikidata.org/wiki/Q11023","display_name":"Engineering","level":0,"score":0.143986314535141},{"id":"https://openalex.org/C170154142","wikidata":"https://www.wikidata.org/wiki/Q150737","display_name":"Architectural engineering","level":1,"score":0.0}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1109/twc.2025.3546927","is_oa":false,"landing_page_url":"https://doi.org/10.1109/twc.2025.3546927","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":[{"id":"https://openalex.org/G5331489779","display_name":null,"funder_award_id":"62221001","funder_id":"https://openalex.org/F4320321001","funder_display_name":"National Natural Science Foundation of China"},{"id":"https://openalex.org/G8663935928","display_name":null,"funder_award_id":"62471027","funder_id":"https://openalex.org/F4320321001","funder_display_name":"National Natural Science Foundation of China"}],"funders":[{"id":"https://openalex.org/F4320321001","display_name":"National Natural Science Foundation of China","ror":"https://ror.org/01h0zpd94"}],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":47,"referenced_works":["https://openalex.org/W1584244501","https://openalex.org/W1969811075","https://openalex.org/W2141682101","https://openalex.org/W2286275639","https://openalex.org/W2788350651","https://openalex.org/W2798701005","https://openalex.org/W2969424089","https://openalex.org/W2974046131","https://openalex.org/W2985994751","https://openalex.org/W3005072086","https://openalex.org/W3084194173","https://openalex.org/W3133817254","https://openalex.org/W3134592264","https://openalex.org/W3199166544","https://openalex.org/W3214334574","https://openalex.org/W4212835306","https://openalex.org/W4221057152","https://openalex.org/W4318586278","https://openalex.org/W4322576964","https://openalex.org/W4323065908","https://openalex.org/W4377079822","https://openalex.org/W4381785979","https://openalex.org/W4382317677","https://openalex.org/W4387869979","https://openalex.org/W4390491928","https://openalex.org/W4390496060","https://openalex.org/W4392151992","https://openalex.org/W4392157642","https://openalex.org/W4392910575","https://openalex.org/W4396505702","https://openalex.org/W4396941274","https://openalex.org/W4397026518","https://openalex.org/W4398151367","https://openalex.org/W4399601919","https://openalex.org/W4399666068","https://openalex.org/W4399666215","https://openalex.org/W4402157133","https://openalex.org/W4402474682","https://openalex.org/W4402915682","https://openalex.org/W4404370900","https://openalex.org/W4404479818","https://openalex.org/W4404688957","https://openalex.org/W4407023187","https://openalex.org/W4408325774","https://openalex.org/W6856567996","https://openalex.org/W6856916424","https://openalex.org/W6870690813"],"related_works":["https://openalex.org/W2111825998","https://openalex.org/W2326544815","https://openalex.org/W2489379490","https://openalex.org/W1973158664","https://openalex.org/W1731022149","https://openalex.org/W1996933839","https://openalex.org/W2000226056","https://openalex.org/W4315778014","https://openalex.org/W4386858283","https://openalex.org/W1979957996"],"abstract_inverted_index":{"Cell-free":[0],"(CF)":[1],"massive":[2],"multiple-input":[3],"multiple-output":[4],"(mMIMO)":[5],"systems":[6,62],"are":[7],"emerging":[8],"as":[9],"promising":[10],"alternatives":[11],"to":[12,34,63,89,122,129,146,164,214,245,271],"cellular":[13],"networks,":[14],"especially":[15],"in":[16,45,77,151,243],"ultra-dense":[17],"environments.":[18],"However,":[19],"further":[20],"capacity":[21],"enhancement":[22,238],"requires":[23],"the":[24,50,78,100,110,124,130,136,152,169,181,193,206,219,224,228,231,236,241,254,260,264,272],"deployment":[25],"of":[26,52,112,135,230,257],"more":[27],"access":[28],"points":[29],"(APs),":[30],"which":[31],"will":[32],"lead":[33],"high":[35,38,133],"costs":[36],"and":[37,116,120,132,184,205,234],"energy":[39],"consumption.":[40],"To":[41],"address":[42],"this":[43,46],"issue,":[44],"paper,":[47],"we":[48,108,139,155,172],"explore":[49],"integration":[51],"low-power,":[53],"low-cost":[54],"stacked":[55],"intelligent":[56],"metasurfaces":[57],"(SIM)":[58],"into":[59,189],"CF":[60],"mMIMO":[61],"enhance":[64],"AP":[65,85,158,201],"capabilities.":[66],"The":[67,249],"key":[68],"point":[69],"is":[70,198,212],"that":[71,179],"SIM":[72,220,258],"performs":[73],"precoding-related":[74],"matrix":[75],"operations":[76],"wave":[79],"domain.":[80],"As":[81],"a":[82,94,141],"consequence,":[83],"each":[84],"antenna":[86,159,202],"only":[87],"needs":[88],"transmit":[90],"data":[91],"streams":[92],"for":[93,102,200,218],"single":[95],"user":[96],"equipment":[97],"(UE),":[98],"eliminating":[99],"need":[101],"complex":[103,194],"baseband":[104],"digital":[105],"precoding.":[106,222],"Then,":[107],"formulate":[109],"problem":[111,188],"joint":[113,182],"AP-UE":[114],"association":[115,161],"precoding":[117,186],"at":[118],"APs":[119],"SIMs":[121],"maximize":[123],"system":[125],"sum":[126,265],"rate.":[127],"Due":[128],"non-convexity":[131],"complexity":[134],"formulated":[137],"problem,":[138],"propose":[140,156],"two-stage":[142],"signal":[143],"processing":[144],"framework":[145,233],"solve":[147],"it.":[148],"In":[149,168],"particular,":[150],"first":[153],"stage,":[154,171],"an":[157,174],"greedy":[160],"(AGA)":[162],"algorithm":[163,178,211,242,262],"minimize":[165],"UE":[166],"interference.":[167],"second":[170],"introduce":[173],"alternating":[175],"optimization":[176,187],"(AO)-based":[177],"separates":[180],"power":[183,203],"wave-based":[185,221],"two":[190],"distinct":[191],"sub-problems:":[192],"quadratic":[195],"transform":[196],"method":[197],"used":[199],"control,":[204],"projection":[207],"gradient":[208],"ascent":[209],"(PGA)":[210],"employed":[213],"find":[215],"suboptimal":[216],"solutions":[217],"Finally,":[223],"numerical":[225],"results":[226,250],"validate":[227],"effectiveness":[229],"proposed":[232,261],"assess":[235],"performance":[237],"achieved":[239],"by":[240,267],"comparison":[244],"various":[246],"benchmark":[247,273],"schemes.":[248],"show":[251],"that,":[252],"with":[253],"same":[255],"number":[256],"meta-atoms,":[259],"improves":[263],"rate":[266],"approximately":[268],"275%":[269],"compared":[270],"scheme.":[274]},"counts_by_year":[{"year":2026,"cited_by_count":13},{"year":2025,"cited_by_count":19}],"updated_date":"2025-12-19T19:40:27.379048","created_date":"2025-10-10T00:00:00"}