标准资料网-标准资料免费资源平台

【英文标准名称】:Luminaires-Part2-14:particularrequirements-Luminairesforcoldcathodetubulardischargelamps(neontubes)andsimilarequipment.
【原文标准名称】:灯具.第2-14部分:详细要求.冷阴极管放电灯(氖管)及类似设备用灯具
【标准号】:NFC71-014-2009
【标准状态】:现行
【国别】:法国
【发布日期】:2009-06-01
【实施或试行日期】:2009-06-06
【发布单位】:法国标准化协会(FR-AFNOR)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:阴极放电灯;尺寸规格;放电灯;电池;电灯;电气工程;荧光灯;照明工程;照明工程学;批注;灯;照明系统;灯具;氖;规范(验收);测试;测试要求;管式放电灯
【英文主题词】:Cathodelamps;Dimensions;Dischargelamps;Electriccells;Electriclamps;Electricalengineering;Fluorescentlamps;Illuminatingengineering;Illuminationengineering;Inscription;Lamps;Lightingsystems;Luminaires;Neon;Specification(approval);Testing;Testingrequirements;Tubulardischargelamps
【摘要】:
【中国标准分类号】:K72
【国际标准分类号】:29_140_40
【页数】:29P;A4
【正文语种】:其他


【英文标准名称】:Methodsofmeasurementforequipmentusedindigitalmicrowaveradiotransmissionsystems-Measurementsonterrestrialradio-relaysystems-Servicechannels
【原文标准名称】:数字微波无线电发射系统使用设备的测量方法.地面无线电中继系统的测量.业务信道
【标准号】:BSEN60835-2-9-1997
【标准状态】:现行
【国别】:英国
【发布日期】:1997-01-15
【实施或试行日期】:1997-01-15
【发布单位】:英国标准学会(GB-BSI)
【起草单位】:BSI
【标准类型】:()
【标准水平】:()
【中文主题词】:模拟;通道;通信系统;定义;定义(术语);数字的;数字工程;数字信号;地面站;电气工程;电气连接件用接口;测量;测量技术;微波链路;无线电信道;无线电电路;无线电工程;无线电器材;无线电通信链路;无线电中继系统;服务终端设备;服务设施;信号;通信;陆地的;传输;传输性能;传输系统
【英文主题词】:Analogue;Channels;Communicationsystems;Definition;Definitions;Digital;Digitalengineering;Digitalsignals;Earthstations;Electricalengineering;Interfacesofelectricalconnections;Measurement;Measuringtechniques;Microwavelinks;Radiochannels;Radiocircuits;Radioengineering;Radioequipment;Radiolinks;Radio-relaysystems;Serviceterminalequipment;Services;Signals;Telecommunication;Terrestrial;Transmission;Transmissionperformance;Transmissionsystems
【摘要】:ThissectionofIEC835-2dealswithmeasurementspertainingtotheservicechannelsusedindigitalmicrowaveradio-relaysystems.Indigitalradio-relaysystems,twobasicmethodsarecommonlyusedforthetransmissionofservicechannelsignals(thatisvoice,supervisoryandcontrolsignals)(seeannexA,ref.[6]).Thefirsttransmissionmethodusesanaloguetransmissiontechniqueswherethei.f.orr.f.carriersignalofthedigitalmodulatorisdirectlyfrequency-modulatedbytheanalogueservicechannelsignal,whichisthenrecoveredatthereceiveendbyanf.m.demodulator(forexampleinthecarrierrecoverycircuitofacoherentdigitaldemodulator).Inthesecondmethodoftransmission,digitaltransmissionisusedandtheservicechannelsignalistransmittedintheformofseparatebitsinsertedintothemainbitstreambyamultiplexer(possiblytogetherwithabitstreamcarryingadditionalinformation).Fordigitaltransmission,theservicechannelsignalmaybeeitherananaloguesignalwhichisdigitallyencodedforbitinsertionoradigitalsignal,inwhichcasesuitablecodeconversionisnormallyappliedinordertoconvertthelinecodeintoacodesuitablefortheradioequipment.Atthereceiveend,ademultiplexerisusedtorecovertheservicechannelbitsandthussupply,aftersuitabledecodingorcodeconversion,theservicechanneloutputsignal.Normally,morethanoneservicechannelistransmitted.Sometimesanadditionalbitstream(forexamplealarmcontrolsignalsforprotectionswitchingandsupervisoryequip-ment)mayalsobetransmitted.Suitablemultiplexinganddemultiplexingequipmentisthenused,suchasfrequencydivisionmultiplexingforanaloguetransmission,andtimedivisionmultiplexingfordigitaltransmission.Theuseoftimedivisionmultiplexingalsoallowsthesimultaneousdigitaltransmissionofanalogueanddigitalservicechannelsignals.Figure1showsthesimultaneousapplicationofalltheabovepossibleservicechanneltransmissionsystems.However,inagivenradio-relaylink,onlyoneortwoofthesesystemsisusedatatime.
【中国标准分类号】:M36
【国际标准分类号】:33_060_30
【页数】:24P.;A4
【正文语种】:英语