{"_buckets": {"deposit": "2fc925b0-2428-45dc-b4b1-468cd6054fd1"}, "_deposit": {"id": "8625", "owners": [], "pid": {"revision_id": 0, "type": "depid", "value": "8625"}, "status": "published"}, "_oai": {"id": "oai:kitami-it.repo.nii.ac.jp:00008625", "sets": ["10"]}, "author_link": ["89928", "89929", "298", "220", "89930", "89931", "89932", "89933", "89934", "89935"], "control_number": "8625", "item_5_biblio_info_6": {"attribute_name": "書誌情報", "attribute_value_mlt": [{"bibliographicIssueDates": {"bibliographicIssueDate": "2014-12-18", "bibliographicIssueDateType": "Issued"}, "bibliographicIssueNumber": "86", "bibliographicPageEnd": "114", "bibliographicPageStart": "109", "bibliographicVolumeNumber": "SIS2014", "bibliographic_titles": [{"bibliographic_title": "電子情報通信学会 信学技報 SIS", "bibliographic_titleLang": "ja"}, {"bibliographic_title": "IEICE Technical Report SIS", "bibliographic_titleLang": "en"}]}]}, "item_5_description_4": {"attribute_name": "抄録", "attribute_value_mlt": [{"subitem_description": "水中音響通信は無線での画像や動画伝送,遠隔操作無人探査機(Remotely Operated Vehicle, ROV)の遠隔操作など様々な用途に利用されている.OFDMはマルチパス干渉に強いが,マルチパスの最大遅延時間に応じてガードインターバル長を設定するので水中音響通信では長遅延のマルチパスにより実効データ伝送速度の低下や受信応答の遅延が問題となる.本研究では水中音響通信で短いガードインターバルでも十分な通信品質を得るための方法としてダイバーシチ技術を検証する.ダイバーシチの信号合成法として最大比合成や選択合成があり,信号対雑音電力比を改善する観点では最大比合成のほうが効果が高いことが知られている.しかしながら,ガードインターバルを超える遅延波が存在する場合は,選択合成が最大比合成よりも改善効果が高い場合があることが検証により明らかとなった.ダイバーシチ技術を組み合わせることで大きな通信特性の改善があり,周波数,空間,時間の3つのダイバーシチ技術を組みわせた時,CN比で20dBの通信特性の改善が得られることを確認した.", "subitem_description_language": "ja", "subitem_description_type": "Abstract"}, {"subitem_description": "Underwater acoustic communication has been widely used in remotely operated vehicle (ROV) and wireless video and image transmission systems. Orthogonal frequency division multiplexing (OFDM) is effective to cope with multipath interference. However, acoustic underwater communication requires a very long guard interval, so which decreases an effective transmission speed and delays a received response. Since OFDM sets a guard interval (GI) in accordance with maximum delay time in multipath, we study various diversity techniques to obtain sufficient communication quality even for a short GI for underwater communications. It is well known that Maximum ratio combining (MRC) is superior to selective combining (SC) in terms of improvement of signal-to-noise ratio (SNR). However, we have found that SC provides better communication performance than MRC on the conditions that a multipath delay exceeds GI and OFDM symbol duration. Moreoever combining diversity techniques in frequency-, space-, and time-domain, shows communication performance improvement of 20-dB in CNR.", "subitem_description_language": "en", "subitem_description_type": "Abstract"}]}, "item_5_publisher_32": {"attribute_name": "出版者", "attribute_value_mlt": [{"subitem_publisher": "電子情報通信学会", "subitem_publisher_language": "ja"}]}, "item_5_rights_12": {"attribute_name": "権利", "attribute_value_mlt": [{"subitem_rights": "c2014 by IEICE"}]}, "item_5_select_15": {"attribute_name": "著者版フラグ", "attribute_value_mlt": [{"subitem_select_item": "publisher"}]}, "item_5_source_id_7": {"attribute_name": "ISSN", "attribute_value_mlt": [{"subitem_source_identifier": "0913-5685", "subitem_source_identifier_type": "PISSN"}]}, "item_access_right": {"attribute_name": "アクセス権", "attribute_value_mlt": [{"subitem_access_right": "open access", "subitem_access_right_uri": "http://purl.org/coar/access_right/c_abf2"}]}, "item_creator": {"attribute_name": "著者", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "石本, 隆太", "creatorNameLang": "ja"}], "nameIdentifiers": [{"nameIdentifier": "89928", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "赤田, 瞬", "creatorNameLang": "ja"}], "nameIdentifiers": [{"nameIdentifier": "89929", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "吉澤 , 真吾", "creatorNameLang": "ja"}], "nameIdentifiers": [{"nameIdentifier": "298", "nameIdentifierScheme": "WEKO"}, {"nameIdentifier": "20447080", "nameIdentifierScheme": "KAKEN - 研究者検索", "nameIdentifierURI": "https://nrid.nii.ac.jp/ja/nrid/1000020447080/"}]}, {"creatorNames": [{"creatorName": "谷本, 洋", "creatorNameLang": "ja"}], "nameIdentifiers": [{"nameIdentifier": "220", "nameIdentifierScheme": "WEKO"}, {"nameIdentifier": "20322886", "nameIdentifierScheme": "KAKEN - 研究者検索", "nameIdentifierURI": "https://nrid.nii.ac.jp/ja/nrid/1000020322886/"}]}, {"creatorNames": [{"creatorName": "齊藤, 隆", "creatorNameLang": "ja"}], "nameIdentifiers": [{"nameIdentifier": "89930", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "ISHIMOTO, Ryuta", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "89931", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "AKADA, Syun", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "89932", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "YOSHIZAWA, Shingo", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "89933", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "TANIMOTO, Hiroshi", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "89934", "nameIdentifierScheme": "WEKO"}]}, {"creatorNames": [{"creatorName": "SAITO, Takashi", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "89935", "nameIdentifierScheme": "WEKO"}]}]}, "item_files": {"attribute_name": "ファイル情報", "attribute_type": "file", "attribute_value_mlt": [{"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2018-02-16"}], "displaytype": "detail", "download_preview_message": "", "file_order": 0, "filename": "SIS2014-86.pdf", "filesize": [{"value": "1.7 MB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_note", "mimetype": "application/pdf", "size": 1700000.0, "url": {"label": "SIS2014-86", "url": "https://kitami-it.repo.nii.ac.jp/record/8625/files/SIS2014-86.pdf"}, "version_id": "e699e68b-9571-4a25-b477-a4c7b4f96191"}]}, "item_keyword": {"attribute_name": "キーワード", "attribute_value_mlt": [{"subitem_subject": "水中音響通信", "subitem_subject_language": "ja", "subitem_subject_scheme": "Other"}, {"subitem_subject": "OFDM", "subitem_subject_language": "en", "subitem_subject_scheme": "Other"}, {"subitem_subject": "ダイバーシチ技術", "subitem_subject_language": "ja", "subitem_subject_scheme": "Other"}, {"subitem_subject": "Underwater acoustic communication", "subitem_subject_language": "en", "subitem_subject_scheme": "Other"}, {"subitem_subject": "OFDM", "subitem_subject_language": "en", "subitem_subject_scheme": "Other"}, {"subitem_subject": "Diversity techniques", "subitem_subject_language": "en", "subitem_subject_scheme": "Other"}]}, "item_language": {"attribute_name": "言語", "attribute_value_mlt": [{"subitem_language": "jpn"}]}, "item_resource_type": {"attribute_name": "資源タイプ", "attribute_value_mlt": [{"resourcetype": "conference paper", "resourceuri": "http://purl.org/coar/resource_type/c_5794"}]}, "item_title": "水中音響OFDM通信におけるダイバーシチ技術の組み合わせ評価 (スマートインフォメディアシステム)", "item_titles": {"attribute_name": "タイトル", "attribute_value_mlt": [{"subitem_title": "水中音響OFDM通信におけるダイバーシチ技術の組み合わせ評価 (スマートインフォメディアシステム)", "subitem_title_language": "ja"}, {"subitem_title": "Evaluation of Diversity Combining Methods for Underwater Acoustic OFDM Communication", "subitem_title_language": "en"}]}, "item_type_id": "5", "owner": "1", "path": ["10"], "permalink_uri": "https://kitami-it.repo.nii.ac.jp/records/8625", "pubdate": {"attribute_name": "PubDate", "attribute_value": "2018-02-16"}, "publish_date": "2018-02-16", "publish_status": "0", "recid": "8625", "relation": {}, "relation_version_is_last": true, "title": ["水中音響OFDM通信におけるダイバーシチ技術の組み合わせ評価 (スマートインフォメディアシステム)"], "weko_shared_id": 3}