{"id":"https://openalex.org/W4392939679","doi":"https://doi.org/10.1109/mwc.007.2300176","title":"Cell-Free XL-MIMO Meets Multi-Agent Reinforcement Learning: Architectures, Challenges, and Future Directions","display_name":"Cell-Free XL-MIMO Meets Multi-Agent Reinforcement Learning: Architectures, Challenges, and Future Directions","publication_year":2024,"publication_date":"2024-03-19","ids":{"openalex":"https://openalex.org/W4392939679","doi":"https://doi.org/10.1109/mwc.007.2300176"},"language":"en","primary_location":{"id":"doi:10.1109/mwc.007.2300176","is_oa":false,"landing_page_url":"https://doi.org/10.1109/mwc.007.2300176","pdf_url":null,"source":{"id":"https://openalex.org/S146764194","display_name":"IEEE Wireless Communications","issn_l":"1536-1284","issn":["1536-1284","1558-0687"],"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","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/A5101405969","display_name":"Zhilong Liu","orcid":"https://orcid.org/0000-0002-0401-5010"},"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":"Zhilong Liu","raw_affiliation_strings":["Beijing Jiaotong University,China"],"affiliations":[{"raw_affiliation_string":"Beijing Jiaotong University,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":["Beijing Jiaotong University,China"],"affiliations":[{"raw_affiliation_string":"Beijing Jiaotong University,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":["Beijing Jiaotong University,China"],"affiliations":[{"raw_affiliation_string":"Beijing Jiaotong University,China","institution_ids":["https://openalex.org/I21193070"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5068782412","display_name":"Hongyang Du","orcid":"https://orcid.org/0000-0002-8220-6525"},"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":"Hongyang Du","raw_affiliation_strings":["Nanyang Technological University,Singapore"],"affiliations":[{"raw_affiliation_string":"Nanyang Technological University,Singapore","institution_ids":["https://openalex.org/I172675005"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5100407664","display_name":"Zhe Wang","orcid":"https://orcid.org/0000-0003-1412-8980"},"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":"Zhe Wang","raw_affiliation_strings":["Beijing Jiaotong University,China"],"affiliations":[{"raw_affiliation_string":"Beijing Jiaotong University,China","institution_ids":["https://openalex.org/I21193070"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5091266202","display_name":"Dusit Niyato","orcid":"https://orcid.org/0000-0002-7442-7416"},"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":"Dusit Niyato","raw_affiliation_strings":["Nanyang Technological University,Singapore"],"affiliations":[{"raw_affiliation_string":"Nanyang Technological University,Singapore","institution_ids":["https://openalex.org/I172675005"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5057916222","display_name":"Mohsen Guizani","orcid":"https://orcid.org/0000-0002-8972-8094"},"institutions":[{"id":"https://openalex.org/I4210113480","display_name":"Mohamed bin Zayed University of Artificial Intelligence","ror":"https://ror.org/0258gkt32","country_code":"AE","type":"education","lineage":["https://openalex.org/I4210113480"]}],"countries":["AE"],"is_corresponding":false,"raw_author_name":"Mohsen Guizani","raw_affiliation_strings":["Mohamed Bin Zayed University of Artificial Intelligence,UAE"],"affiliations":[{"raw_affiliation_string":"Mohamed Bin Zayed University of Artificial Intelligence,UAE","institution_ids":["https://openalex.org/I4210113480"]}]},{"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":["Beijing Jiaotong University,China"],"affiliations":[{"raw_affiliation_string":"Beijing Jiaotong University,China","institution_ids":["https://openalex.org/I21193070"]}]}],"institutions":[],"countries_distinct_count":3,"institutions_distinct_count":8,"corresponding_author_ids":["https://openalex.org/A5101405969"],"corresponding_institution_ids":["https://openalex.org/I21193070"],"apc_list":null,"apc_paid":null,"fwci":9.7879,"has_fulltext":false,"cited_by_count":45,"citation_normalized_percentile":{"value":0.98661793,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":89,"max":100},"biblio":{"volume":"31","issue":"4","first_page":"155","last_page":"162"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11458","display_name":"Advanced Wireless Communication Technologies","score":1.0,"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":1.0,"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/T10148","display_name":"Advanced MIMO Systems Optimization","score":0.9991000294685364,"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/T11392","display_name":"Energy Harvesting in Wireless Networks","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"}}],"keywords":[{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.785839319229126},{"id":"https://openalex.org/keywords/reinforcement-learning","display_name":"Reinforcement learning","score":0.7656525373458862},{"id":"https://openalex.org/keywords/mimo","display_name":"MIMO","score":0.6033979058265686},{"id":"https://openalex.org/keywords/computer-architecture","display_name":"Computer architecture","score":0.3448750972747803},{"id":"https://openalex.org/keywords/distributed-computing","display_name":"Distributed computing","score":0.33266472816467285},{"id":"https://openalex.org/keywords/computer-network","display_name":"Computer network","score":0.3068535327911377},{"id":"https://openalex.org/keywords/artificial-intelligence","display_name":"Artificial intelligence","score":0.2855494022369385},{"id":"https://openalex.org/keywords/channel","display_name":"Channel (broadcasting)","score":0.13159766793251038}],"concepts":[{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.785839319229126},{"id":"https://openalex.org/C97541855","wikidata":"https://www.wikidata.org/wiki/Q830687","display_name":"Reinforcement learning","level":2,"score":0.7656525373458862},{"id":"https://openalex.org/C207987634","wikidata":"https://www.wikidata.org/wiki/Q176862","display_name":"MIMO","level":3,"score":0.6033979058265686},{"id":"https://openalex.org/C118524514","wikidata":"https://www.wikidata.org/wiki/Q173212","display_name":"Computer architecture","level":1,"score":0.3448750972747803},{"id":"https://openalex.org/C120314980","wikidata":"https://www.wikidata.org/wiki/Q180634","display_name":"Distributed computing","level":1,"score":0.33266472816467285},{"id":"https://openalex.org/C31258907","wikidata":"https://www.wikidata.org/wiki/Q1301371","display_name":"Computer network","level":1,"score":0.3068535327911377},{"id":"https://openalex.org/C154945302","wikidata":"https://www.wikidata.org/wiki/Q11660","display_name":"Artificial intelligence","level":1,"score":0.2855494022369385},{"id":"https://openalex.org/C127162648","wikidata":"https://www.wikidata.org/wiki/Q16858953","display_name":"Channel (broadcasting)","level":2,"score":0.13159766793251038}],"mesh":[],"locations_count":2,"locations":[{"id":"doi:10.1109/mwc.007.2300176","is_oa":false,"landing_page_url":"https://doi.org/10.1109/mwc.007.2300176","pdf_url":null,"source":{"id":"https://openalex.org/S146764194","display_name":"IEEE Wireless Communications","issn_l":"1536-1284","issn":["1536-1284","1558-0687"],"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","raw_type":"journal-article"},{"id":"pmh:oai:hub.hku.hk:10722/353140","is_oa":false,"landing_page_url":"https://hub.hku.hk/handle/10722/353140","pdf_url":null,"source":{"id":"https://openalex.org/S4377196271","display_name":"The HKU Scholars Hub (University of Hong Kong)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I889458895","host_organization_name":"University of Hong Kong","host_organization_lineage":["https://openalex.org/I889458895"],"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":null,"sustainable_development_goals":[],"awards":[{"id":"https://openalex.org/G1807731908","display_name":null,"funder_award_id":"BK20212002","funder_id":"https://openalex.org/F4320322769","funder_display_name":"Natural Science Foundation of Jiangsu Province"},{"id":"https://openalex.org/G3561954627","display_name":null,"funder_award_id":"2020YFB1807201","funder_id":"https://openalex.org/F4320335777","funder_display_name":"National Key Research and Development Program of China"},{"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/G6416229212","display_name":null,"funder_award_id":"2023YJS001,2022JBQY004","funder_id":"https://openalex.org/F4320335787","funder_display_name":"Fundamental Research Funds for the Central Universities"}],"funders":[{"id":"https://openalex.org/F4320320709","display_name":"National Research Foundation Singapore","ror":"https://ror.org/03cpyc314"},{"id":"https://openalex.org/F4320321001","display_name":"National Natural Science Foundation of China","ror":"https://ror.org/01h0zpd94"},{"id":"https://openalex.org/F4320322769","display_name":"Natural Science Foundation of Jiangsu Province","ror":"https://ror.org/01h0zpd94"},{"id":"https://openalex.org/F4320335777","display_name":"National Key Research and Development Program of China","ror":null},{"id":"https://openalex.org/F4320335787","display_name":"Fundamental Research Funds for the Central Universities","ror":null}],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":15,"referenced_works":["https://openalex.org/W3034448035","https://openalex.org/W3038830320","https://openalex.org/W3041653465","https://openalex.org/W3084857938","https://openalex.org/W3091365446","https://openalex.org/W3213225772","https://openalex.org/W4226168441","https://openalex.org/W4297094903","https://openalex.org/W4312515423","https://openalex.org/W4312985348","https://openalex.org/W4321636817","https://openalex.org/W4323651193","https://openalex.org/W4324125657","https://openalex.org/W4364322798","https://openalex.org/W4386260512"],"related_works":["https://openalex.org/W4306904969","https://openalex.org/W2138720691","https://openalex.org/W4362501864","https://openalex.org/W4380318855","https://openalex.org/W2031695474","https://openalex.org/W2024136090","https://openalex.org/W2586732548","https://openalex.org/W3049728571","https://openalex.org/W2964765435","https://openalex.org/W4391331176"],"abstract_inverted_index":{"Cell-free":[0],"massive":[1],"multiple-input":[2],"multiple-output":[3],"(mMIMO)":[4],"and":[5,47,81,107,117],"extremely":[6],"large-scale":[7],"MIMO":[8],"(XL-MIMO)":[9],"are":[10,137],"regarded":[11],"as":[12],"promising":[13],"innovations":[14],"for":[15,73],"the":[16,28,44,56,75,87,99,119],"forthcoming":[17],"generation":[18],"of":[19,30,32,59,77,98],"wireless":[20],"communication":[21],"systems.":[22,52],"Their":[23],"significant":[24],"advantages":[25],"in":[26,91],"augmenting":[27],"number":[29],"degrees":[31],"freedom":[33],"have":[34],"garnered":[35],"considerable":[36],"interest.":[37],"In":[38],"this":[39],"article,":[40],"we":[41,94],"first":[42],"review":[43],"essential":[45],"opportunities":[46],"challenges":[48],"induced":[49],"by":[50],"XL-MIMO":[51,92,115,135],"We":[53],"then":[54],"propose":[55,95],"enhanced":[57],"paradigm":[58],"cell-free":[60,114,134],"XL-MIMO,":[61],"which":[62],"incorporates":[63],"multi-agent":[64],"reinforcement":[65],"learning":[66],"(MARL)":[67],"to":[68,110,112,132],"provide":[69],"a":[70],"distributed":[71],"strategy":[72],"tackling":[74],"problems":[76],"high-dimensional":[78],"signal":[79],"processing":[80],"costly":[82],"energy":[83],"consumption.":[84],"Based":[85],"on":[86],"unique":[88],"near-field":[89],"characteristics":[90],"systems,":[93],"two":[96],"categories":[97],"low-complexity":[100],"algorithm":[101],"design,":[102],"that":[103],"is,":[104],"antenna":[105],"selection":[106],"power":[108],"control,":[109],"adapt":[111],"different":[113],"scenarios":[116],"meet":[118],"increasing":[120],"data":[121],"rate":[122],"requirements.":[123],"For":[124],"inspiration,":[125],"several":[126],"critical":[127],"future":[128],"research":[129],"directions":[130],"pertaining":[131],"green":[133],"systems":[136],"presented.":[138]},"counts_by_year":[{"year":2026,"cited_by_count":2},{"year":2025,"cited_by_count":24},{"year":2024,"cited_by_count":18},{"year":2023,"cited_by_count":1}],"updated_date":"2026-02-25T08:12:03.925757","created_date":"2025-10-10T00:00:00"}