Agilent網(wǎng)絡(luò)分析儀原理及使用

1、page 1page 2page 3雙功器LO LC 濾波器功分器TX IF LC濾波器耦合器隔離器平衡/非平衡轉(zhuǎn)換混頻器LNA放大器SAW 濾波器SAW 濾波器天線射頻前端模塊平衡/非平衡轉(zhuǎn)換page 4 Lightwave入射入射反射反射透射透射 RF/MWpage 5 Gain, Phase, Group delay VSWR, , , Impedancel 工作頻率工作頻率; 信號功率信號功率page 6 dB全匹配全匹配(ZL = Zo) RLVSWR01全反射全反射 (ZL = 開路開路,短路短路 )0 dB1=ZL-ZOZL+OZ=V反射V輸入=F= -20 log(),VSWR

2、 = EmaxEmin=1 + 1 - EmaxEmin (功率比值功率比值)page 7 0+R+jX-jXRectilinear impedance plane.-90o0o180o+-.2.4.6.81.090o 0 0等電抗圓等電抗圓等電阻圓等電阻圓Smith Chart 圓圖上圓圖上 一點(diǎn)一點(diǎn)位置反映對應(yīng)的位置反映對應(yīng)的阻抗阻抗(R+jx)和和反射反射(模和相位模和相位)LZ = 0=180 O1(短路點(diǎn)短路點(diǎn)) Z = L=0 O1(開路點(diǎn)開路點(diǎn)) Z = ZoL= 0大電阻區(qū)大電阻區(qū)小電阻區(qū)小電阻區(qū)電感區(qū)電感區(qū)電容區(qū)電容區(qū) Z=R+jx Z=R+jx page 8RL / RSR

3、SRLRL = RS: 負(fù)載上最大功率傳輸負(fù)載上最大功率傳輸 Zs = R + jXZL = Zs* = R - jX ZL = ZS* (共軛匹配共軛匹配)RL / RS00.20.40.60.811.2012345678910Load Power (normalized)page 9V傳輸V輸入傳輸系數(shù)傳輸系數(shù) = T T=VTransmittedVIncident = tf tfDUT增益增益 (dB) = 20 Log VTrans VInc = 20 log t t插入損耗插入損耗 (dB) = - 20 Log VTrans VInc = - 20 log t tpage 10Ti

4、meAtoFrequencyf1TimeSin 360 * f * tFrequencyA phase shift = to * 360 * f1fDUT A * Sin 360 * f ( t - t )輸入輸入輸出輸出TimeFrequencyf1page 11系統(tǒng)頻率帶寬內(nèi)幅頻特性為常量系統(tǒng)頻率帶寬內(nèi)幅頻特性為常量MagnitudePhaseFrequencyFrequency系統(tǒng)頻率帶寬內(nèi)相頻特性為線性系統(tǒng)頻率帶寬內(nèi)相頻特性為線性 V = a f( t - to)輸出輸出V = f(t)輸入輸入DUTpage 12網(wǎng)絡(luò)分析儀相位補(bǔ)償網(wǎng)絡(luò)分析儀相位補(bǔ)償+=Frequency(Electr

5、ical delay )FrequencyPhase 1 /DivoPhase 45 /DivoFrequency 應(yīng)用應(yīng)用: 測量器件相位特性 難于定量分析相位特性線性 應(yīng)用應(yīng)用: 便于對相位特性線性的分析網(wǎng)絡(luò)分析儀的相位補(bǔ)償處理功能：網(wǎng)絡(luò)分析儀的相位補(bǔ)償處理功能： page 13in radiansin radians/secin degreesf in Hertz (w = 2 p f)fwfGroup Delay (t )g =-d fd w=-1360od fd f*Frequency群時(shí)延抖動(dòng)群時(shí)延抖動(dòng)平均時(shí)延平均時(shí)延totg PhasefDfFrequencyDwwpage 14

6、PhasePhaseGroup DelayGroup Delay- -d f fd w w- -d f fd w wffffpage 15TransmittedIncident傳輸特性傳輸特性增益增益S參數(shù)參數(shù)S21,S12群延時(shí)群延時(shí)Delay傳輸系數(shù)傳輸系數(shù)相位相位PhaseReflectedIncident反射特性反射特性SWRS參數(shù)參數(shù)S11,S22反射系數(shù)反射系數(shù)阻抗阻抗 R+jX, G+jB 反射損耗反射損耗 , , T,tT,t輸入輸入反射反射輸出輸出RBAAR=BR=page 16S11=ReflectedIncident=b1a1a2= 0S21=TransmittedInc

7、ident=b2a1a2= 0S22=ReflectedIncident=b2a2a1= 0S12=TransmittedIncident=b1a2a1= 0輸入輸入傳輸傳輸S21S11反射反射b1a1b2Z0Loada2= 0DUT正向正向輸入輸入傳輸傳輸S12S22反射反射b2a2ba1= 0DUTZ0Load反向反向1S-parameters 電壓線性值定義電壓線性值定義page 17FrequencyFrequencyTimeTimepage 18CH1 S21 1og MAG 1 dB/ REF 32 dB 30.991 dB 12.3 dBmC2 IF BW 3 kHz SWP 4

8、20 msecSTART 5 5dBm CW 902 MHz STOP 15 dBm1 dB compression point: 輸入功率增加導(dǎo)致器件增益下降輸入功率增加導(dǎo)致器件增益下降1dBl相對測試相對測試l輸出輸出1dB壓縮點(diǎn)壓縮點(diǎn)(絕對測試絕對測試) 測試功率測試功率 測試頻率測試頻率01dB 輸入輸入1dB壓縮點(diǎn)壓縮點(diǎn)page 19飽和工作電平飽和工作電平壓縮工作區(qū)壓縮工作區(qū)線性工作區(qū)線性工作區(qū) (slope = small-signal gain)1dBpage 20AmplitudeTimeAM (dB)PM (deg)Mag(AMin)Test StimulusAmplitu

9、deTimeAM (dB)PM (deg)Mag(AMout)Mag(PMout)Output ResponseAM - PM Conversion =Mag(PMout)Mag(AMin)(deg/dB)DUTPower sweepIQAM to PM conversion can cause bit errors輸入功率對器件相位特性的影響輸入功率對器件相位特性的影響page 21Port 2功率分配/開關(guān)源R1APort 1R2B衰減器衰減器測量接收機(jī)參考接收機(jī)參考接收機(jī)反射信號(A)傳輸信號(B)輸入信號輸入信號輸出信號輸出信號DUT信號源信號源信號分離裝置信號分離裝置接收機(jī)接收機(jī)處理

10、顯示單元處理顯示單元RAB輸入源輸入源LO 源源RFN*LO +/- IF反射反射傳輸傳輸輸入?yún)⒖夹盘栞斎雲(yún)⒖夹盘栞斎胄盘栞斎胄盘栞敵鲂盘栞敵鲂盘朆RARl提供被測件激勵(lì)信號提供被測件激勵(lì)信號l具備具備頻率和功率掃描頻率和功率掃描功能功能l合成源實(shí)現(xiàn)合成源實(shí)現(xiàn)頻率合成源頻率合成源ALCALCDriverALC 檢測檢測衰減器衰減器源源ALC = 自動(dòng)電平控制自動(dòng)電平控制 (automatic level control)l功分器功分器提供參考信號提供參考信號寬頻率覆蓋寬頻率覆蓋6 dB50 W50 W6 dBl定向耦合器定向耦合器l電橋電橋方向性方向性低插入損耗低插入損耗Main signal

11、Coupled signalRECEIVER / DETECTORPROCESSOR / DISPLAYREFLECTED(A)TRANSMITTED(B)INCIDENT (R)SIGNALSEPARATIONSOURCEIncidentReflectedTransmittedDUT 定向耦合器連接端點(diǎn)定向耦合器連接端點(diǎn): 反射特性測試點(diǎn)反射特性測試點(diǎn)Test PortDetector(入射信號泄漏入射信號泄漏)(被測件反射方向被測件反射方向)定向耦合器定向耦合器(定向耦合器輸入端定向耦合器輸入端)Data MaxAdd in PhaseDeviceDirectivityReturn Los

12、sFrequency03060DUT RL = 40 dBCancel Data 0DeviceDirectivityData = Vector SumDirectivityDeviceData Min 被測件反射信號被測件反射信號與定向耦合器泄漏的與定向耦合器泄漏的 輸入信號輸入信號在接收機(jī)端矢量疊加在接收機(jī)端矢量疊加 影響測試精度影響測試精度接收機(jī)類型Tuned ReceiverScalar broadband (no phase information)Vector(magnitude and phase)DiodeDCACRFIF FilterIF = F LOFRFRFLOADC /

13、 DSPRECEIVER / DETECTORPROCESSOR / DISPLAYREFLECTED(A)TRANSMITTED(B)INCIDENT (R)SIGNALSEPARATIONSOURCEIncidentReflectedTransmittedDUT300kHz8.5 GHz混頻器前端混頻器前端ADC / DSP幅度幅度+相位信息相位信息接收機(jī)帶寬接收機(jī)帶寬 :70kHz-100dBError Due to Interfering Signal0.0010.010.11101000-5-10-15-20-25-30-35-40-45-50-55-60-65-70Interfer

14、ing signal (dB)Error (dB, deg)phase errormagn error+-網(wǎng)絡(luò)分析儀測試精度與測試動(dòng)態(tài)范圍關(guān)系網(wǎng)絡(luò)分析儀測試精度與測試動(dòng)態(tài)范圍關(guān)系T/R vs S-Parameter Test SetslRF always comes out port 1lport 2 is always receiverlresponse, one-port cal availablelRF comes out port 1 or port 2lforward and reverse measurementsltwo-port calibration possibleTran

15、smission/Reflection Test SetPort 1Port 2SourceBRADUTFwdPort 1Port 2Transfer switchSourceBRAS-Parameter Test SetDUTFwdRevRECEIVER / DETECTORPROCESSOR / DISPLAYREFLECTED(A)TRANSMITTED(B)INCIDENT (R)SIGNALSEPARATIONSOURCEIncidentReflectedTransmittedDUTAB負(fù)載失配負(fù)載失配串?dāng)_串?dāng)_方向性誤差方向性誤差DUT頻率響應(yīng)誤差頻率響應(yīng)誤差l傳輸跟蹤誤差傳輸跟蹤誤差R 單端口共單端口共 6 項(xiàng)誤差項(xiàng)誤差 雙端口共雙端口共 12 項(xiàng)誤差項(xiàng)誤差 反射信號反射信號l S11MS11ASHORTOPENLOADthruthruSHORTOPENLOAD電子校準(zhǔn)件電子校準(zhǔn)件(Ecal)機(jī)械校準(zhǔn)件機(jī)械校準(zhǔn)件校準(zhǔn)件多次連接校準(zhǔn)件多次連接Shorts, Open, Loads, Thru單次連接；多端口校準(zhǔn)單次連接；多端口校準(zhǔn)Single Connection 不校準(zhǔn)不校準(zhǔn) 2. 頻響校準(zhǔn)頻響校準(zhǔn) 3. 1-PORT單端校準(zhǔn)單端校準(zhǔn) 4. FULL 2-PORT雙端校準(zhǔn)雙端校準(zhǔn)l復(fù)雜,校準(zhǔn)件多次連接l高精度l消除測試中所有