{"id":"https://openalex.org/W4386766437","doi":"https://doi.org/10.1109/lgrs.2023.3315839","title":"Efficient Maximum-Likelihood Estimation of Equivalent Number of Looks for PolSAR Image","display_name":"Efficient Maximum-Likelihood Estimation of Equivalent Number of Looks for PolSAR Image","publication_year":2023,"publication_date":"2023-01-01","ids":{"openalex":"https://openalex.org/W4386766437","doi":"https://doi.org/10.1109/lgrs.2023.3315839"},"language":"en","primary_location":{"id":"doi:10.1109/lgrs.2023.3315839","is_oa":false,"landing_page_url":"https://doi.org/10.1109/lgrs.2023.3315839","pdf_url":null,"source":{"id":"https://openalex.org/S126920919","display_name":"IEEE Geoscience and Remote Sensing Letters","issn_l":"1545-598X","issn":["1545-598X","1558-0571"],"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 Geoscience and Remote Sensing 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/A5004739506","display_name":"Xianxiang Qin","orcid":"https://orcid.org/0000-0002-1760-2396"},"institutions":[{"id":"https://openalex.org/I17145004","display_name":"Northwestern Polytechnical University","ror":"https://ror.org/01y0j0j86","country_code":"CN","type":"education","lineage":["https://openalex.org/I17145004"]}],"countries":["CN"],"is_corresponding":true,"raw_author_name":"Xianxiang Qin","raw_affiliation_strings":["School of Computer Science, Northwestern Polytechnical University, Xi’an, China"],"affiliations":[{"raw_affiliation_string":"School of Computer Science, Northwestern Polytechnical University, Xi’an, China","institution_ids":["https://openalex.org/I17145004"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5028235866","display_name":"Yanning Zhang","orcid":"https://orcid.org/0000-0002-2977-8057"},"institutions":[{"id":"https://openalex.org/I17145004","display_name":"Northwestern Polytechnical University","ror":"https://ror.org/01y0j0j86","country_code":"CN","type":"education","lineage":["https://openalex.org/I17145004"]}],"countries":["CN"],"is_corresponding":false,"raw_author_name":"Yanning Zhang","raw_affiliation_strings":["School of Computer Science, Northwestern Polytechnical University, Xi’an, China"],"affiliations":[{"raw_affiliation_string":"School of Computer Science, Northwestern Polytechnical University, Xi’an, China","institution_ids":["https://openalex.org/I17145004"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5100785617","display_name":"Ying Li","orcid":"https://orcid.org/0000-0001-7370-1754"},"institutions":[{"id":"https://openalex.org/I17145004","display_name":"Northwestern Polytechnical University","ror":"https://ror.org/01y0j0j86","country_code":"CN","type":"education","lineage":["https://openalex.org/I17145004"]}],"countries":["CN"],"is_corresponding":false,"raw_author_name":"Ying Li","raw_affiliation_strings":["School of Computer Science, Northwestern Polytechnical University, Xi’an, China"],"affiliations":[{"raw_affiliation_string":"School of Computer Science, Northwestern Polytechnical University, Xi’an, China","institution_ids":["https://openalex.org/I17145004"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":3,"corresponding_author_ids":["https://openalex.org/A5004739506"],"corresponding_institution_ids":["https://openalex.org/I17145004"],"apc_list":null,"apc_paid":null,"fwci":0.8824,"has_fulltext":false,"cited_by_count":2,"citation_normalized_percentile":{"value":0.8103654,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":{"min":91,"max":99},"biblio":{"volume":"20","issue":null,"first_page":"1","last_page":"5"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10801","display_name":"Synthetic Aperture Radar (SAR) Applications and Techniques","score":0.9998000264167786,"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/T10801","display_name":"Synthetic Aperture Radar (SAR) Applications and Techniques","score":0.9998000264167786,"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/T10500","display_name":"Sparse and Compressive Sensing Techniques","score":0.988099992275238,"subfield":{"id":"https://openalex.org/subfields/2206","display_name":"Computational Mechanics"},"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/T11038","display_name":"Advanced SAR Imaging Techniques","score":0.9832000136375427,"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/estimator","display_name":"Estimator","score":0.8214466571807861},{"id":"https://openalex.org/keywords/wishart-distribution","display_name":"Wishart distribution","score":0.6206063032150269},{"id":"https://openalex.org/keywords/image","display_name":"Image (mathematics)","score":0.5600839257240295},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.5139179229736328},{"id":"https://openalex.org/keywords/estimation-theory","display_name":"Estimation theory","score":0.49910783767700195},{"id":"https://openalex.org/keywords/pixel","display_name":"Pixel","score":0.4990427494049072},{"id":"https://openalex.org/keywords/minimum-variance-unbiased-estimator","display_name":"Minimum-variance unbiased estimator","score":0.46382203698158264},{"id":"https://openalex.org/keywords/variance","display_name":"Variance (accounting)","score":0.4612198770046234},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.43976590037345886},{"id":"https://openalex.org/keywords/distribution","display_name":"Distribution (mathematics)","score":0.43890097737312317},{"id":"https://openalex.org/keywords/bias-of-an-estimator","display_name":"Bias of an estimator","score":0.4258570373058319},{"id":"https://openalex.org/keywords/statistics","display_name":"Statistics","score":0.4013028144836426},{"id":"https://openalex.org/keywords/algorithm","display_name":"Algorithm","score":0.39845308661460876},{"id":"https://openalex.org/keywords/artificial-intelligence","display_name":"Artificial intelligence","score":0.3628333806991577},{"id":"https://openalex.org/keywords/pattern-recognition","display_name":"Pattern recognition (psychology)","score":0.3588011860847473},{"id":"https://openalex.org/keywords/applied-mathematics","display_name":"Applied mathematics","score":0.3397771418094635}],"concepts":[{"id":"https://openalex.org/C185429906","wikidata":"https://www.wikidata.org/wiki/Q1130160","display_name":"Estimator","level":2,"score":0.8214466571807861},{"id":"https://openalex.org/C33962027","wikidata":"https://www.wikidata.org/wiki/Q1930697","display_name":"Wishart distribution","level":3,"score":0.6206063032150269},{"id":"https://openalex.org/C115961682","wikidata":"https://www.wikidata.org/wiki/Q860623","display_name":"Image (mathematics)","level":2,"score":0.5600839257240295},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.5139179229736328},{"id":"https://openalex.org/C167928553","wikidata":"https://www.wikidata.org/wiki/Q1376021","display_name":"Estimation theory","level":2,"score":0.49910783767700195},{"id":"https://openalex.org/C160633673","wikidata":"https://www.wikidata.org/wiki/Q355198","display_name":"Pixel","level":2,"score":0.4990427494049072},{"id":"https://openalex.org/C165646398","wikidata":"https://www.wikidata.org/wiki/Q3755281","display_name":"Minimum-variance unbiased estimator","level":3,"score":0.46382203698158264},{"id":"https://openalex.org/C196083921","wikidata":"https://www.wikidata.org/wiki/Q7915758","display_name":"Variance (accounting)","level":2,"score":0.4612198770046234},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.43976590037345886},{"id":"https://openalex.org/C110121322","wikidata":"https://www.wikidata.org/wiki/Q865811","display_name":"Distribution (mathematics)","level":2,"score":0.43890097737312317},{"id":"https://openalex.org/C191393472","wikidata":"https://www.wikidata.org/wiki/Q15222032","display_name":"Bias of an estimator","level":4,"score":0.4258570373058319},{"id":"https://openalex.org/C105795698","wikidata":"https://www.wikidata.org/wiki/Q12483","display_name":"Statistics","level":1,"score":0.4013028144836426},{"id":"https://openalex.org/C11413529","wikidata":"https://www.wikidata.org/wiki/Q8366","display_name":"Algorithm","level":1,"score":0.39845308661460876},{"id":"https://openalex.org/C154945302","wikidata":"https://www.wikidata.org/wiki/Q11660","display_name":"Artificial intelligence","level":1,"score":0.3628333806991577},{"id":"https://openalex.org/C153180895","wikidata":"https://www.wikidata.org/wiki/Q7148389","display_name":"Pattern recognition (psychology)","level":2,"score":0.3588011860847473},{"id":"https://openalex.org/C28826006","wikidata":"https://www.wikidata.org/wiki/Q33521","display_name":"Applied mathematics","level":1,"score":0.3397771418094635},{"id":"https://openalex.org/C121955636","wikidata":"https://www.wikidata.org/wiki/Q4116214","display_name":"Accounting","level":1,"score":0.0},{"id":"https://openalex.org/C144133560","wikidata":"https://www.wikidata.org/wiki/Q4830453","display_name":"Business","level":0,"score":0.0},{"id":"https://openalex.org/C134306372","wikidata":"https://www.wikidata.org/wiki/Q7754","display_name":"Mathematical analysis","level":1,"score":0.0},{"id":"https://openalex.org/C161584116","wikidata":"https://www.wikidata.org/wiki/Q1952580","display_name":"Multivariate statistics","level":2,"score":0.0}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1109/lgrs.2023.3315839","is_oa":false,"landing_page_url":"https://doi.org/10.1109/lgrs.2023.3315839","pdf_url":null,"source":{"id":"https://openalex.org/S126920919","display_name":"IEEE Geoscience and Remote Sensing Letters","issn_l":"1545-598X","issn":["1545-598X","1558-0571"],"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 Geoscience and Remote Sensing Letters","raw_type":"journal-article"}],"best_oa_location":null,"sustainable_development_goals":[],"awards":[{"id":"https://openalex.org/G6556306731","display_name":null,"funder_award_id":"62271400","funder_id":"https://openalex.org/F4320321001","funder_display_name":"National Natural Science Foundation of China"},{"id":"https://openalex.org/G6569676177","display_name":null,"funder_award_id":"2021M702672","funder_id":"https://openalex.org/F4320321543","funder_display_name":"China Postdoctoral Science Foundation"},{"id":"https://openalex.org/G7763695145","display_name":null,"funder_award_id":"2023-GHZD-02","funder_id":"https://openalex.org/F4320336350","funder_display_name":"Key Research and Development Projects of Shaanxi Province"}],"funders":[{"id":"https://openalex.org/F4320321001","display_name":"National Natural Science Foundation of China","ror":"https://ror.org/01h0zpd94"},{"id":"https://openalex.org/F4320321543","display_name":"China Postdoctoral Science Foundation","ror":"https://ror.org/0426zh255"},{"id":"https://openalex.org/F4320336350","display_name":"Key Research and Development Projects of Shaanxi Province","ror":null}],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":19,"referenced_works":["https://openalex.org/W1421632428","https://openalex.org/W1985194020","https://openalex.org/W2028961524","https://openalex.org/W2093258516","https://openalex.org/W2103836868","https://openalex.org/W2109900939","https://openalex.org/W2126413832","https://openalex.org/W2143353454","https://openalex.org/W2157985480","https://openalex.org/W2588704026","https://openalex.org/W2913335421","https://openalex.org/W3147919432","https://openalex.org/W4213370452","https://openalex.org/W4237764598","https://openalex.org/W4293057170","https://openalex.org/W4300223101","https://openalex.org/W4300905642","https://openalex.org/W4309741576","https://openalex.org/W4320726935"],"related_works":["https://openalex.org/W2349547417","https://openalex.org/W4237435333","https://openalex.org/W4210503132","https://openalex.org/W2999390738","https://openalex.org/W2352602506","https://openalex.org/W3092888124","https://openalex.org/W4239491110","https://openalex.org/W2368191880","https://openalex.org/W2910434125","https://openalex.org/W2035998077"],"abstract_inverted_index":{"The":[0,121],"complex":[1,41],"Wishart":[2,42],"distribution":[3],"is":[4,23,51,55,65,75,143],"a":[5,24,105,154,163],"widely":[6],"used":[7],"statistical":[8],"model":[9],"for":[10],"multilook":[11],"PolSAR":[12,106,126,164],"image":[13,165],"data,":[14],"of":[15,20,40,44,90,104,162],"which":[16,45],"the":[17,28,38,46,101,116,138,159],"equivalent":[18],"number":[19],"looks":[21],"(ENL)":[22],"critical":[25],"parameter.":[26],"Over":[27],"past":[29],"decades,":[30],"various":[31],"estimators":[32],"have":[33],"been":[34],"developed":[35],"to":[36,99,114,157],"estimate":[37,100,158],"ENL":[39,91,102,135,160],"distribution,":[43],"maximum":[47],"likelihood":[48],"(ML)":[49],"estimator":[50,64,89,141],"important":[52],"since":[53,68],"it":[54,69],"asymptotically":[56],"unbiased":[57],"and":[58,74],"has":[59,70],"small":[60],"variance.":[61],"However,":[62],"this":[63,81,83],"very":[66],"time-consuming":[67],"no":[71],"analytical":[72],"solution":[73],"usually":[76],"solved":[77],"numerically.":[78],"To":[79],"address":[80],"problem,":[82],"letter":[84],"proposes":[85],"an":[86,94,111],"efficient":[87,112],"ML":[88,140],"by":[92],"deriving":[93],"approximate":[95,134],"closed-form":[96],"solution.":[97],"Moreover,":[98],"map":[103,161],"image,":[107],"we":[108],"also":[109],"develop":[110],"way":[113],"compute":[115],"local":[117],"sample":[118],"statistics":[119],"parallelly.":[120],"experimental":[122],"results":[123],"on":[124,153],"two":[125],"images":[127],"show":[128],"that":[129],"our":[130],"method":[131],"yields":[132],"highly":[133],"values":[136],"as":[137],"traditional":[139],"while":[142],"much":[144],"more":[145],"efficient.":[146],"It":[147],"costs":[148],"less":[149],"than":[150],"0.8":[151],"seconds":[152],"general":[155],"laptop":[156],"with":[166],"900\u00d71024":[167],"pixels.":[168]},"counts_by_year":[{"year":2026,"cited_by_count":1},{"year":2025,"cited_by_count":1}],"updated_date":"2025-11-06T03:46:38.306776","created_date":"2025-10-10T00:00:00"}