CISPR-22--内-容-重-点-for-Albert-Lai

CISPR22內容重點Preparedby:HW_ALBERT_LAI簡介資訊類產品的電磁干擾特性之量測方法與限制值Informationtechnologyequipment---Radiodisturbancecharacteristics---Limitsandmethodsofmeasurement測試規範CISPR22:1997EN55022:1998CNS13438C63537:1997VCCICLASSII/ITE:1999/5AS/NZS3548:1995規範差異CISPR22:1997,EN55022:1998&CNS13438:1997差異在於增加通訊埠傳導干擾檢測(ISN測試)(ISN測試,已通告延後自2005年8月開始實施)範圍與目的適用於資訊技術產品(ITE:InformationTechnologyEquipment)規定ITE所產生之介於9kHz-400GHz之附混波(Spurioussignals)信號的限制值及檢測程序.產品分類:將ITE分為兩類,表示為ClassA&CLASSBClassBITE:符合ClassBITE是指主要設計使用於住宅環境之產品.其可能包括:--無固定使用場所,例如:電池供電式之可攜式設備--由通信網路供電之通信終端設備--個人電腦及其輔助連接設備CLASSAITE:符合CLASSAITE擾動限制值但不符合CLASSB限制值之產品此類產品之銷售將不受限制但須有下列警語在使用手冊中Warning:ThisisaClassAproduct.Inadomesticenvironmentthisproductmaycauseradiointerferenceinwhichcasetheusermayberequiredtotakeadequatemeasure.測量的方法:所量測到的電磁干擾強度是以dB(uv/m)為單位.一般是用頻譜分析儀,在無響隔離室(AnechoicChamber),以峰值偵測器(PeakDetector),掃瞄全頻段的頻譜,是否有超過準靜峰值(Quasi-peak)的界限或是低於6dB的準靜峰值的界限.若超過,再用測試接收器(TestReceiver),針對超出界限的單點頻率,以準靜峰值偵測器,在開闊場地(OpenTestSite),調整轉盤從0到360度,與天線上下從1米到4米,找到並記錄最大的準靜峰讀值.頻譜分析儀和測試接收器要符合CISPR16-1:1993的標準.電源端和通信埠之傳導干擾限制值如果量測到的Quasi-peak值已符合Average限制值時,則可視為已同時符合Average值且不須再測Average.若量測接收機讀值非常接近限制值且變動不定時,則此時該頻率點讀值須觀察15秒以上並記錄其最高讀值(短暫突波不計)電源端傳導干擾限制值Table1---LimitsforconducteddisturbanceatmainsportsofclassAITELimitsdB(uV)FrequencyrangeMHzQuasi-peakAverage0.15to0.5079660.50to307360Note:ThelowerlimitshallapplyatthetransitionfrequencyTable2---LimitsforconducteddisturbanceatmainsportsofclassBITELimitsdB(uV)FrequencyrangeMHzQuasi-peakAverage0.15to0.5066to5656to460.50to556465to306050Note1:ThelowerlimitshallapplyatthetransitionfrequencyNote2:Thelimitdecreaseslinearlywiththelogarithmofthefrequencyintherange0.15MHzto0.50MHzTable3---Limitsofconductedcommonmode(asymmetricmode)disturbanceattelecommunicationportsinthefrequencyrange0.15MHzto30MHzforclassAequipmentVoltagelimitsdB(uV)CurrentlimitsdB(uV)FrequencyrangeMHzQuasi-peakAverageQuasi-peakAverage0.15to0.597to8784to7453to4340to300.5to3087744330NOTE1:ThelimitsdecreaselinearlywithlogarithmofthefrequencyinTherange0.15MHzto0.5MHz.NOTE2:ThecurrentandvoltagedisturbancelimitsarederivedforUseWithanimpedancestabilizationnetwork(ISN)whichpresentsacommonmode(asymmetricmode)impedanceof150tothetelecommunicationportundertest(conversionfactoris20log10150/1=44dB)Table4---Limitsofconductedcommonmode(asymmetricmode)disturbanceattelecommunicationportsinthefrequencyrange0.15MHzto30MHzforclassBequipmentVoltagelimitsdB(uV)CurrentlimitsdB(uV)FrequencyrangeMHzQuasi-peakAverageQuasi-peakAverage0.15to0.584to7474to6440to3030to200.5to3074643020NOTE1:Thelimitsdecreaselinearlywithlogarithmofthefrequencyintherange0.15MHzto0.5MHz.NOTE2:Thecurrentandvoltagedisturbancelimitsarederivedforusewithanimpedancestabilizationnetwork(ISN)whichpresentsacommonmode(asymmetricmode)impedanceof150tothetelecommunicationportundertest(conversionfactoris20log10150/1=44dB)NOTE3:6MHzto30MHzstillnotconfirmyet.輻射擾動限制值若量測接收機的讀值非常接近限制值且變動不定時,則此時該頻率點讀值須觀察15秒以上並記錄其最高讀值(短暫突波不計)Table5:LimitsforradiateddisturbanceofclassAITEatameasuringdistanceof10MFrequencyrangeMHzQuasi-peaklimitsdB(uV/m)30to23040230to100047NOTE1:Thelowerlimitshallapplyatthetransitionfrequency,NOTE2:Additionalprovisionsmayberequiredforcaseswhereinterferenceoccurs.Table6:LimitsforradiateddisturbanceofclassBITEatameasuringdistanceof10MFrequencyrangeMHzQuasi-peaklimitsdB(uV/m)30to23030230to100037NOTE1:Thelowerlimitshallapplyatthetransitionfrequency,NOTE2:Additionalprovisionsmayberequiredforcaseswhereinterferenceoccurs.CISPR限制值的意義從統計的基礎上來看,至少要有80%的信心度,相信大量生產的設備至少要有80%的產品符合此限制值.•必須從量產品中以隨機取樣的方式,常常對產品做後續的測試.一般測試條件一個測試場地,必須足以分辨ITE所產生的擾動及外部的雜訊.一個合適的場地當待測設備未開機時其外部的雜訊強度必須低於相對限制值6Db以上.但當某些頻段無法滿足此要求時,需用其它方式來判別待測物(EUT)是否符合規定.若外部雜訊加上待測物所產生的擾動兩者總合低於限制值時,外部雜訊可不低於限制值6dB以上,且視為此量測值符合規定的限制值若外部雜訊加上待測物所產生的擾動兩者總合高於限制值時,不可直接判斷待測物不合格,除非該量測頻率符合下列兩個條件:A.外界雜訊強度低於外界雜訊和設備所產生的擾動的總合6dB以上.B.外界雜訊強度須低於相對應的限制值4.8dB以上.場地介紹:Opensite:3M&10MSemi-anechoicchamber:9*6*6M&10MShieldingroom:9*6*6M&7*4*3MTheopentestsitefor3and10mintroduction根據ANSI63.7–1988,CISPR16–1-1993和GB/T6113.1–1995規定了開闊試驗場地的構造特徵，它是一個平坦的，空曠的，電導率均勻良好的，無任何反射物的楕圓形試驗場地，其長軸是二焦點距離的２倍，短軸是焦距的Γ３倍，發射天線（或待測物）與接收天線分別置於楕圓的二焦點上。R2RTheopentestsitefor3and10mintroductionTheSemi-anechoicchamberfor3mintroductionLinkouEMCequippedwithasemianechoicchamber,whichis7X4X3M.ThischamberadoptsfoamastheabsorbertomeettheCE&FCCstandard.Thetestingtablesaremadefromlow-reflectingmaterialtoguaranteethetestingaccuracy(e.g.Radiationmeasuring).TheBi-Logandhornantennaareusedasthetestingantennastocoverafrequencyrangeof30MHzto10GHz.TheoscillationiseliminatedbywayofspecialarrangementofantennasTheSemi-anechoicchamberfor3mintroductionTheSemi-anechoicchamberfor3mintroductionTheShieldingroomwithferritetilefor3mintroductionOneshieldedrooms(7X4X3M)withFerritetileforEMIRadiationandConductiontest.ThisshieldingroomwithferritetileastheabsorbertomeettheCE&FCCstandard.Thetestingtablesaremadefromlow-reflectingmaterialtoguaranteethetestingaccuracy(e.g.Radiationmeasuring).TheBi-Logandhornantennaareusedasthetestingantennastocoverafrequencyrangeof30MHzto