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辦公室光信道用光連接器檢測項目報價???解決方案???檢測周期???樣品要求? |
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本標準為光纖分布式數(shù)據(jù)接口(FDDI)規(guī)定了物理層媒體相關(guān)部分(PMD)的要求。 FDDI使用光纖作為傳輸媒體,為計算機和外圍設(shè)備之間提供一個高帶寬(100Mbit/s)的通用互連。FDDI可配置來支持大約80Mbit/s(10Mbyte/s)的持續(xù)傳送速率,它可能不能滿足所有無緩沖的高速設(shè)備的響應(yīng)時間要求。FDDI建立分布于幾千米的許多FDDI結(jié)點之間的連接。FDDI的默認值是按1000條物理鏈路和總長為200Km的光纖通路計算的。 FDDI由以下幾部分組成: 物理層(PL),它分成兩個子層: 物理層媒體相關(guān)部分(PMD),為FDDI網(wǎng)絡(luò)結(jié)點間提供數(shù)字基帶點對點通信手段。PMD應(yīng) 提供在結(jié)點間傳送一個經(jīng)適當編碼的比特流所需的各種服務(wù)。PMD規(guī)定了媒體接口連 接器(MIC)兩側(cè)符合 FDDI站及光纜裝置要求的互連點。PMD由下列部分組成: --使用62.5/125um光纜和光旁路開關(guān)的光纜裝置的光功率預(yù)算。 --MIC插座的機械匹配要求,包括鍵瑣特性。 --62.5/125um光纜要求。 --PMD各PHY和SMT提供的服務(wù)。 物理層協(xié)議(PHY),它在PMD和數(shù)據(jù)鏈路層(DLL)之間提供連接。PHY對上游編碼比特 數(shù)據(jù)流建立時鐘同步,并把到達的代碼比特流解碼成高層使用的等效符號流。PHY在數(shù)據(jù) 及控制指示符的符號和代友比特之間提供了編碼和解碼,提供媒體調(diào)節(jié)和初始化,提供入 和出代碼比特的時鐘同步,以及按去往或來自較高層信息傳輸要求提供八位位組邊界定 界。在接口媒體上待發(fā)送的信息由PHY編碼成為組成的傳輸代碼。 數(shù)據(jù)鏈路層(DLL),它控制媒的訪問和幀校驗序列的生成和驗證,以確保有效數(shù)據(jù)正確地交付給其他導(dǎo)。在FDDI網(wǎng)絡(luò)中,DLL也關(guān)心設(shè)備地址的生成和識別以及同層對同層的聯(lián)系。對于本標準而言,引用DLL是通過媒體訪問控制(MAC)實體來進行的,此實體是DLL低子層。 站管理(SMT)<上標1)>,它在結(jié)點級上提供必要的控制,以便管理各種不同的FDDI層中正在進行的進程,使得結(jié)點可以在令牌環(huán)上協(xié)調(diào)地工作。SMT提供諸如配置管理的控制、故障隔離與恢復(fù),以及過程調(diào)度等服務(wù)。 本標準是GB/T16678.1的支持文件,應(yīng)結(jié)合該標準一起閱讀。 SMT文件應(yīng)作為支持FDDI結(jié)點和網(wǎng)絡(luò)配置的參考信息。 本系列標準規(guī)定了必要的接口、功能和操作,以確保在符合FDDI的實現(xiàn)之間的互操作性。本標準是一種功能描述,與之相符合的實現(xiàn)可以利用任何不違反互操作性的設(shè)計技術(shù)
GB/T 17564的本部分在公共字典內(nèi)規(guī)定: ——電工設(shè)備和系統(tǒng)用電氣元器件和材料的數(shù)據(jù)元素類型定義;——元器件類別及相關(guān)分類模式的定義;這些定義與電氣元器件(包括電子、機電元器件和電工設(shè)備及系統(tǒng)中用的材料)有關(guān)。本部分的目的是用下列方式提供唯一標識的數(shù)據(jù)元素類型集:——定義的內(nèi)容準確無歧義;——規(guī)定的值格式;——非定量數(shù)據(jù)元素類型的規(guī)定值域。元器件分類模式、元器件類別定義(通過特定數(shù)據(jù)元素類型將相關(guān)和有效的特性特征分配給每類元器件)用來準確元歧義定義數(shù)據(jù)元素類型并且使整個數(shù)據(jù)元素類型集可管理。本部分的數(shù)據(jù)元素類型集預(yù)定用于計算機化系統(tǒng)進行元器件選擇與元器件管理、零部件列表處理以及計算機輔助設(shè)計、制造和測試。
本部分規(guī)定了建筑及居住區(qū)數(shù)字化技術(shù)應(yīng)用的檢測內(nèi)容、方法和驗收要求等,包括通信系統(tǒng)、信息系統(tǒng)與監(jiān)控系統(tǒng)以及支持這些系統(tǒng)工程的基礎(chǔ)設(shè)施(包括:信息網(wǎng)絡(luò)平臺、綜合布線系統(tǒng)、電源與接地、環(huán)境、機房系統(tǒng)、基礎(chǔ)系統(tǒng)集成等)的檢測驗收。 本部分適用于對建筑及居住區(qū)數(shù)字化技術(shù)應(yīng)用系統(tǒng)的功能與質(zhì)量的第三方檢測,相應(yīng)的改擴建系統(tǒng)和其他應(yīng)用項目可以參照使用。
本標準規(guī)定了傳輸速率為千兆比(1 G)和萬兆比(10 G)的基于以太網(wǎng)方式的無源光網(wǎng)絡(luò)[EPON]系統(tǒng)的互通性測試方法,包括EPON基本功能互通性、業(yè)務(wù)承載相關(guān)功能互通性、操作管理和維護功能互通性的測試方法。本標準適用于FTTH/FTTO場景下的EPON設(shè)備。FTTB場景下的EPON設(shè)備也可參考使用。
本規(guī)范適用于新建、擴建、改建建筑與建筑群綜合布線系統(tǒng)工程設(shè)計。
本規(guī)范適用于新建的大、中型水電廠和抽水蓄能電廠的通信設(shè)計。本規(guī)范規(guī)定了水電廠通信系統(tǒng)設(shè)計的基本原則及主要技術(shù)要求。
本標準規(guī)定了在接入網(wǎng)功能結(jié)構(gòu)、系統(tǒng)和設(shè)備、接入網(wǎng)技術(shù)中出現(xiàn)的基本名詞術(shù)語。本標準適用于接入網(wǎng)研究、開發(fā)、運行和維護中名詞術(shù)語的解釋、翻譯和應(yīng)用。
本標準規(guī)定了光纖到戶(RTTH,F(xiàn)iber To The Home)的體系架構(gòu)及總體要求,包括FTTH系統(tǒng)的體系架構(gòu)、網(wǎng)絡(luò)拓撲、支持的業(yè)務(wù)類型、實現(xiàn)技術(shù)與要求、性能指標要求以及運行和維護要求等,概要地規(guī)范了FTTH用光纜及線路輔助設(shè)施的基本要求。 本標準適用于在我國公用電信網(wǎng)中FTTH用戶接入的網(wǎng)絡(luò)(包括系統(tǒng)設(shè)備、線路及相關(guān)配套設(shè)施),專用電信網(wǎng)亦可參照本標準。
本部分規(guī)定了傳輸匯聚(TC)層采用GPON封裝模式(GEM)的吉比特的無源光網(wǎng)絡(luò)(GPON)系統(tǒng)的參考模型、設(shè)備功能結(jié)構(gòu)、光網(wǎng)絡(luò)要求、業(yè)務(wù)承載能力性能指標、業(yè)務(wù)接口類型、功能與協(xié)議、保護與安全、操作維護管理以及設(shè)備電氣安全等方面的要求。本部分適用于公眾電信網(wǎng)環(huán)境下的GPON設(shè)備,專用電信網(wǎng)也可參照使用。
本部分規(guī)定了無線通信室內(nèi)信號分布系統(tǒng)(簡稱室內(nèi)分布系統(tǒng))的組建總體原則、網(wǎng)絡(luò)結(jié)構(gòu)、網(wǎng)絡(luò)性能、總體技術(shù)要求、設(shè)備及工程安裝設(shè)計技術(shù)要求等。本部分適用于共用或獨立建設(shè)無線通信室內(nèi)分布系統(tǒng),包括GSM、cdma2000、TD-SCDMA、WCDMA、cdma2000 HRPD、無線接入、集群、數(shù)字多媒體廣播等信號的室內(nèi)接入覆蓋,其它無線室內(nèi)分布系統(tǒng)也可參考本部分。
《波分復(fù)用(WDM)光纖傳輸系統(tǒng)工程設(shè)計規(guī)范》(以下簡稱“本規(guī)范”)適用于單纖單向開放式粗波分復(fù)用系統(tǒng)和C波段單纖單向開放式密集波分復(fù)用系統(tǒng)的工程設(shè)計。當本規(guī)定與有關(guān)標準(規(guī)范)相矛盾時,應(yīng)按標準(規(guī)范)的相關(guān)規(guī)定辦理。在特殊條件下,執(zhí)行本規(guī)范中的個別條款有困難時,應(yīng)充分論述理由,提出采取措施的報告,呈主管部門審批。
This standard will encompass two levels of interface, defining operation overdistances less than 10 m. The physical layer will specify electrical, mechanical, and thermalcharacteristics of connectors and cards. The logical level will describe the address space,data transfer protocols, cache coherence mechanisms, synchronization primitives, control andstatus registers, and initialization and error recovery facilities.
This Recommendation covers the data structure and dual link serial interface for 525/625-line digital signalsas defined in Recommendation ITU-R BT.601-5.
Readers of this Report should be aware that the text in this Report is the original text generated during the development of the SDTV digital interfaces. It is has been retained as an historic record of the digital interface development.
This Report presents an overview of Inspections Procedures in response to Question ITU-R 225/1 regarding inspection techniques and procedures. The Question relates to how administrations proceed in planning and conducting radio station inspections. The purpose of this Report is to provide general guidelines for planning and performing inspection activities on various types of radio stations. Inspection activities often include review and verification of both technical and administrative conditions assigned to a radio station or other spectrum user. Although the term “l(fā)icensed” is used throughout the document, this term can be considered here to include not only stations with licences issued by the regulatory authority, but also other authorized spectrum users (such as those operating with “l(fā)icence exempt” devices like low-power radios and RF devices operating under equipment standards approval). The primary focus of this report is to consider inspections that are conducted “on-site”, by visiting the transmitter location. Included in Annexes are some specific examples in certain services, toprovide examples of howthe general guidelines can be applied. This Report should be considered a general guidance document for inspections planning.
This Recommendation specifies the media aspects of the interfaces between IPCablecom clientdevices for audio and video communication. Specifically, it identifies the audio and video codecsnecessary to provide the highest quality and the most resource-efficient service delivery to thecustomer. This Recommendation also specifies the performance required in client devices tosupport future IPCablecom codecs. Additionally, this Recommendation describes a suggestedmethodology for optimal network support for codecs.1.1 Introduction and overviewThe quality of audio and video delivered over the IPCablecom architecture will depend on multiplefactors: the end device performance, the network's inherent quality, and the intelligence of thesystem resource allocation policy. This Recommendation specifies codecs and capabilitiessupporting audio and video applications, with a particular emphasis on the stringent requirements ofIP-based voice communications.Acceptable voice communications functionality imposes strict delay and packet-loss criteria on IPimplementations and will thus stress system resources, particularly if bandwidth becomes congestedor saturated. Video applications – while more forgiving to dropped packets and delay – requirebandwidth of at least an order of magnitude more than audio applications. The IPCablecomarchitecture is designed to support both voice and video applications simultaneously.Speech and video compression are evolving technologies. New algorithms are being enabled as moresophisticated and higher performing processors become available at lower cost. Additionally, thesystem infrastructure and mechanisms for allocating resources will evolve. Due to this dynamism, thepriority in designing the architecture is to define a robust system to accommodate evolvingtechnology without creating a legacy burden.Therefore, the IPCablecom philosophy is to establish cost-effective envelopes for network and deviceperformance to enable the most appropriate current technology, while allowing upgrades astechnology and market needs evolve. To address near-term market needs, this Recommendation alsospecifies codec and performance mandates to deliver the quality-of-service necessary for launchingcompetitive services.1.2 Purpose of this RecommendationThe purpose of this Recommendation is to extend the existing IPCablecom v1CodecRecommendation by introducing two new low-bit codecs, [ITU-T T.38] fax relay for reliable faxtransmission, [IETF RFC 2833] DTMF Relay for reliable DTMF transmission and metrics tomeasure voice quality. It is issued to facilitate design and field-testing leading to themanufacturability and interoperability of conforming hardware and software by multiple vendors.1.3 Phasing of requirementsThe codec requirements contained in this Recommendation cover both audio and video multimediaterminals (MTAs) and trunking gateways (media gateway). The term MTA-2 is used to define aterminal supporting video.In the initial phase of IPCablecom, MTAs are not required to support the MTA-2 requirements asdefined in clause 8. MTAs MUST support the requirements for audio terminals as defined inclauses 5, 6, 7, and 9.Support for video terminals will be REQUIRED in later phases of IPCablecom. All MTA-2s MUSTsupport the requirements defined in clause 8.
This Recommendation mainly describes the maintenance band and requirements for maintenancetest light filtering (such as cut-off bandwidth, isolation and other optical characteristics) for testingin-service fibre lines without interfering with optical communication signals in access networks.L.66 provides guidance on the use of an out-of-band remote test system. An alternative approach isto monitor key parameters of the transmission equipment, such as the OLT transmitted power andthe ONU received power, but this approach is not examined in this Recommendation.
This Recommendation describes the functional requirements of optical fibre cable maintenancesystems for optical fibre cable carrying a high total optical power. It applies to test equipment,optical switches for selecting a test fibre, test access modules for connecting test equipment to thecommunication line, testing optical fibre cords and optical connecting devices that are contained inthe maintenance system. It also considers safety procedures and guidelines for the maintenance ofoutside optical fibre plant carrying a high total optical power.